วันพฤหัสบดีที่ 21 เมษายน พ.ศ. 2554

dna mapping

dna mapping

The discovery of the existence of DNA has not been enough for scientists since there is more part of the puzzle to be revealed. For instance, to fully understand human existence, genetics and heredity, every gene on the human chromosome has to be determined including their function and the function for their placement. This process is called DNA Mapping, a very complex and intricate means to dig deep everything about the human Deoxyribose Nucleic Acid.

DNA Mapping has a variety of purposes. The human life is reliant on DNA, on every pairing of bases, arrangement of genes and chromosomes. Any mismatch, missing piece or extra piece can be fatal to a person. Errors can even cause the death of an unborn child. If not, the baby can die shortly after birth or become disfigured or predisposed to certain diseases all the day of his or her life. The human DNA is still so mysterious, yet slowly, scientists are able to unravel minute details. A complete information can save a lot of lives, prevent reproduction and development problems as well as find cures for untreatable conditions. The success of this procedure can also prove evolution. It can pinpoint certain mutations which brought improvements to the form, figure and functioning of the human body from its believed ape ancestor. It can also enable scientists to explain the differences in human race- why there are Asians, Caucasians and Negroids if there is only one breed of human ancestry. It can even link humans to other animals and to the human ecosystem where he lives.

Indeed, DNA mapping can complete the human puzzle. The difficulty in figuring out every gene and chromosome along with their respective functions just prove how progressive and unique humans are. It is like figuring out every wiring on the boards of the computers so it can work and deliver its purpose. Any slight deviation can bring about a defect or give another function. For instance, a scientist jokingly says that mismatches can make a gorilla, earthworm or elephant instead. As such, the quest for the human existence will only be completed with the unraveling of the DNA blunders.

By:Lindsey_Jenkins
Article Source: dna mapping


automated dna sequencing

automated dna sequencing

Why is DNA Analysis important to me?

Knowing your family's genetic history may someday save your life or that of someone you love. Based on state-of-the-art genetic technology, a unique DNA Profile can be generated for you to keep for years to come. DNA Storage for up to 25 years is available for future genetic testing, upon your request. What better gift can a loved one leave behind?

What role does DNA have in Funeral Service?

The purpose of this article is to familiarize Funeral Directors about DNA activities, and related areas. Realizing that this technology is what we as caregivers are used to discussing, is a field that is of concern to many of our clients and their families. The vast spectrum of DNA can give us insight on the value it can play in our community. In a series of articles, we would like to give you a basic knowledge about the different but related studies involving DNA.

It takes three generations to determine predisposition to most of the genetic inherited diseases / disorders. It is now known that families should store DNA for future use. Banking specimens containing DNA from the same Family provides invaluable information for the health of current and future offspring. We as Funeral Directors have an opportunity to make a Family aware that such a service is available. After burial, retrieving DNA can be expensive. Obtaining DNA after cremation is much more difficult. The success rate of recovering DNA within the first year of cremation is approximately 50%. Offering storage and or profiling DNA of the deceased, gives Funeral Directors a Unique opportunity to offer a Service that can have a lasting impact on those we serve. If you as a Funeral Director do not see the need for this service, it does not mean that families do not need this service. Statistics tell us that families place a tremendous amount of trust in their Funeral Director. This is because we care so deeply in what we do. Informing a Family of their options, while guiding them through the most difficult times in their life is a responsibility that a Funeral Director accepts and excels in.

It is our hope that Funeral Homes throughout the United States will contact us and give us their input as to the value of DNA in a Funeral service.

Why we firmly believe in what we do.

At the National Funeral Directors Association meeting in October 2001, we outlined all the reasons for the value of DNA storage such as paternity/inheritance, genealogy, missing persons, forensic issues; identification of hereditary disorders, congenital birth defects; predisposition to allergies, mental, metabolic, cardiovascular, bleeding/clotting disorders, genetic cancers, microbial diseases. The potential does not end with the above. Rapidly evolving technologies in cloning pets, stem cell/gene therapy are currently being done, all to improve the quality of life.

Recently we had four interesting success stories...

1. A 62-year-old female dies of complications resulting from Breast Cancer. The deceased women leave 2 daughters and 1 granddaughter. During a "Pre-Need Consultation", the woman elected to have her DNA profiled and the sample banked.

2 years later; one of the daughters is diagnosed with the same Breast Cancer as the Mother. The second daughter has her DNA profiled and compared to the mothers. It is determined that the second daughter does not have the same genetic structure as the mother that would pre-dispose her to the cancer. However, the Granddaughters DNA is profiled and it is determined that she possesses the same genetic disorder as the Grandmother. Pharmacogenomics and gene therapy are begun to prevent the cancer in the granddaughter before it develops.

2. The mother of a Divorced son was interested in identifying the granddaughter's father. Was he her husband were her son? We identified her son is the alleged father. This was a "Paternity" issue.

3. The three sons of the deceased lady came to request identification of their mothers remains between two occupants of a gravesite that had collapsed. She passed away seven years ago, so the atypical specimen sources were bone marrow and vertebrae. Procedures were laborious, but we identified their mother. Her remains can now be transferred to another site. This is "Profiling".

4. A friend's baby presented with what appeared to be a Bleeding tendency at 3 months of age. The baby was admitted to Children's Hospital, Cincinnati, extensively treated but expired at age 8 months. An autopsy revealed universal capillary involvement (small blood vessels) by a clotting abnormality resulting in damaging complications in vital organs such as heart, liver and spleen. This leaves a Protein called von Willebrand factor and is coded by a Gene called ADAMSTS 13. The parents are currently being tested for "Mutations" in order to know who transmitted to the gene. The baby's DNA is currently in storage it doesn't matter who stores DNA in life and in death provided it is properly collected and stored because although it's stable, it can be contaminated and it can disappear during purification; this complicates genetic testing. Before the advent of Pharmacogenomics, astute clinicians treating HIV patients relied on drug resistance testing to predict outcomes; complementary to resistance testing his current genotyping, which includes identifying mutations, associated with resistance. In the not-too-distant future, the combination of drug resistance testing and pharmacokinetic testing will provide a better idea of in-vivo relevance of resistance data. Stored DNA lasts forever; it will provide an endless source for multiple testing that will hopefully improve clinical outcomes.

Pharmacogenomics

The terms "Pharmacogenomics" and "Pharmacokinetics" are sometimes used interchangeably to describe the analysis of genes involved in drug response.

Pharmacogenomics is more inclusive; it refers not only to the effects of individual genes, but also to complex interaction between genes from every part of the genome affecting drug response.

Pharmacogenomics is an aid to diagnosis and prognosis. Routine diagnosis is not always straightforward. A patient does not always come with textbook type symptoms of the disease. In some cases, a single gene variation has been shown to be responsible for disease, and a Genetic test for this scan confirms the diagnosis as in cystic fibrosis and Huntington's disease. Sometimes more than one gene is involved, such as to Breast Cancer genes, Alzheimer's Disease genes, and susceptibility to Migraine genes. The most likely publicly visible contribution of Pharmacogenomics to improved health care would be delivery of a number of drugs coupled to diagnostic tests based on genetic markers for head and neck, pancreatic cancers, and solid tumors.

Pharmacogenomics classifies patients into responders and non-responders to particular therapeutic options. Breast cancers that over express a Protein for the herceptin genes are candidates for monoclonal antibody therapy. The cholesterol-lowering drug PRAVACHOL works according to the number of copies of the transfer protein gene. HIV Phenotyping is an important and practical adjunct to the treatment of AIDS.

Pharmacogenomics can save lives lost to adverse drug events, the 6th leading cause of death in the US. A blood test now enables physicians to tailor a certain drug dosage to their patient's genetic profiles. However, the cause and effect association remains unknown. Implementation of rapid automated DNA genotyping capabilities still, over time, provides individual genotypes of patients. Clinical data that is properly collected and managed identifies patient subpopulations at risk for adverse events, while allowing others to continue to receive the benefits of pharmaceutical therapy.

Pharmacogenomics and Gene Therapy

Mutation is a change of DNA sequence leading to aberrant or absent expression of the corresponding protein. It is the mutation, not the gene that causes predisposition to disorder/disease. Polymorphism is the quality of existing in several different forms. Sequencing of parts of the genome has demonstrated that some of these polymorphisms are in genes whose functions are important in responses of individual patient to therapy. The pathologist will need to profile common polymorphisms in patients who are beginning therapy for common diseases such as diabetes, hypertension, cancer and infections. The laboratory definition of the genotype/phenotype will determine the specific drug and doses suitable for him. This puts the pathologist in a more definitive position to determine appropriate therapy than traditional predictions of disease behavior based on morphology of lesions (microscopic patterns) or cultural characteristics of infectious organisms. The lab also monitors the success of gene therapy. After a gene is introduced, the tissue where the gene is inserted (i.e.: Transgenic Monkey or Mouse) must be active and should be monitored for normal expression of the introduced gene and normal structure and function of the gene product. The lab must also monitor the "integrating transfected genes" such that integration allows both normal gene expression and does not produce abnormal function or structure of the patient's other genes. In summary, molecular pathology is permeating and penetrating, as was immunopathology 20 years ago. "Immunopathology" an example of which is vaccine therapy is nothing new, a German/Austrian vaccine "UKRAIN" is supposed to destroy cancer cells through APOPTOSOS (programmed cell death) without attacking healthy cells. The US now has "GLEEVAC" with identical results. It also has been proven that in breast cancers there are genetically divergent CLONES that account for different microscopic components resulting in different responses to therapy.

Future Direction

As the human genome Project continues to uncover important disease genes (especially those for common disorders) at an ever increasing rate and technologies for high-speed DNA sequencing and multiplex mutation detection continued to improve, we can anticipate diagnostic molecular genetics assuming a far more dominant role in public health and preventive medicine. The advance of DNA "CHIPS" containing thousands of probes may someday allow extensive genotyping and lifetime disease prediction for thousands of disorders from a single drop of blood. Also, a poster on Human Genome Landmarks in the US Department of Energy, identifies a whole gamut of diseases/disorders with the corresponding position of the defective gene! Against these promising advances will have to be weighed ethical issues, especially in the field of gene therapy. Whatever the ultimate balance reached, there's no doubt that molecular genetics will be the driving force behind an ever greater proportion of evidence based medical practice in the 21st century and virtually every patient whether healthy or ill will feel the impact.

The impact of DNA storage on clinical practice
Evidence based medicine is the gold standard for the 21st century.

What do we do that contributes to the practice of this medicine? What specific examples and daily living indicate that storing DNA is a "Must"?

The event of 9/11 mainly profiling and identifying the deceased was laborious and expensive on federal funds despite which only approximately 2000 persons have been identified. One does not realize the importance of the death certificate without which burial cannot be accomplished until death occurs! Soldiers "missing in action" cannot be declared dead until their bodies are found and identified.

An article in USA Today concerned a "Mystery killer" that involved a young couple; studies failed to give a definitive answer despite autopsy and numerous laboratory tests. Since chances that the suspected disease that clinically presented to be contagious (plague) proved negative on repeated testing. Had DNA been stored, further testing may have led to the diagnosis and cause of death

A TV program about a Serial killer in Juarez Mexico led to more than 200 missing women and "no leads". Profiling and storing of DNA when these women were newborns would have helped identify the remains that took months to surface. The women after being raped were doused with gasoline and burned! The problem is ongoing.

Although Chandra Levy was missing for a year before the body was found, DNA is stable, and after profiling samples from her remains she can now be laid to rest. Since degraded DNA is difficult to purify, tests on her remains are ongoing to hopefully identify the killer. The FBI in USA Today declared, "there still are no clues to the killer". Samples are from her remains such as hair, teeth, bone; even old blood can still be stored and tested along with a Suspect's samples until results are conclusive.

A complex disease such as Parkinson's disease and the genes whose polymorphic forms can increase any person's risk but not necessarily cause it is the second most common in a Neuron-degenerative disorder. Parkinson's disease has neither a Polygenic (multiple genes) or multifactoral (genes and environment) cause. Over the past few years, debate has occurred between Parkinson's disease having a Genetic component or is just secondary to environmental influences. To evaluate the possible genetic component, open quote gene mapping" is the way to go. The availability of data from the Human Genome Project is opening new possibilities in studying common diseases such as Parkinson's disease. The multitude of molecular techniques and statistical tools applied to this data now allows us to potentially move medicine from a "reactive" discipline to one that can prevent disease. However, once found, how these "susceptibility genes" will be used in the future remains to be seen.

A newborn (the 3rd child) was diagnosed to have a "Rare protein allergy". Surgery was successful the baby is now seven years of age and healthy. Two other siblings are healthy. Storing this baby's DNA would have enabled testing of future siblings for mutations related to this rare congenital predisposition to allergies.

At three months of age a Baby presented with a Bleeding disorder; she was admitted, traded and died at the Children's Hospital in Cincinnati. The baby's profile showed a defective ADAMSTS 13 gene. The parents are being tested for this "mutation" and the baby's blood, buccal smears, and hairs are stored.

Will everyone be gene type early in life to prevent disease that they are at risk for? How will this affect employment/applications for competitive educational opportunities? Wolf farm code genetic genotyping be routine to determine patients with the risk for side effects or variability in efficacy? If the patient refuses typing will third-party payers is still pay for medications and/or treatment? Someday mandatory DNA storage and testing in life and death will enhance the quality of life and improve clinical outcomes because increasing knowledge of genetic variations sheds light on the role of genetic and environmental factors and disease susceptibility, aggression and therapeutic response.

Specialists can now screen eggs for the faulty gene that closes early onset Alzheimer's disease, enabling women who carry their rare disorder to avoid passing it on to their children.

FDA approved GLEEVEC has been very effective in chronic myelogenous leukemia and rare (stromal) stomach cancers; causes of relapse do so because they have developed mutations that alter GLEEVEC's target site in the leukemic cells, a Phenomenon well known to infectious disease clinicians. Just as microbes developing drug resistance mutations, so do cancer cells.

Summarizing the future of cancer treatment: in the past, pathologic diagnosis was based on histology. In the future it will be based on molecular profiling of tissue both that the genetic and proteinomic level. In the past, therapy was chosen by disease category. In the future, combination therapy will be aimed in tailored to individual patient profiles or classes of profiles. Select, monitor, and reevaluate.. that's hope for the future!

Scott Nizborski is the President and Owner of LabEx, Inc. LabEx is an authorized represetative for DNA Analysis providing DNA Profiling and Storage Services focused on the Funeral Pre-Need business.

By:Scott_Nizborski

Article Source: automated dna sequencing


วันเสาร์ที่ 16 เมษายน พ.ศ. 2554

dna results

dna results
DNA testing is a powerful tool and in some cases a very controversial tool, especially when immigration DNA testing is used for relatives from other countries to enter the US more easily and legally.

The tests have been used for thousands of US residents that want to sponsor a relative into the country but for one reason or another they do not possess a birth certificate or any other identification to prove they are related. This is where immigration DNA testing comes into play.

US government officials will recognize and accept DNA testing to allow the entry of these individuals. But here's where the problem comes in and even immigration lawyers are becoming very concerned. The problem is that government officials are requiring DNA testing more and more, even when the paperwork is all in place and there is no reason.

Immigration DNA testing has a few concerns. For starters it increases the cost a lot and it slows down the entire process. The second concern is the government itself and just how much they can be trusted. What exactly is happening with all these DNA results. Many believe this information is being turned over to agencies like Homeland Security where it is tracked in large databases.

There were just short of a million people who obtained permanent residency or a temporary visa last year as a result of being directly related to a US citizen.

Homeland Security officials claim that the DNA information is not retained but there is some evidence that this isn't true. There are only a couple of labs in the country that are authorized to do immigration DNA testing so although potential immigrants may request DNA testing from another type of lab such as the AABB it will not be recognized by the government.

Immigration lawyers believe it is these two labs in Washington that are actually driving the increase in the requests for DNA testing. After all for a private lab what a great source of revenue.

The concerns began to arise as more and more immigration requests that have all the necessary paperwork and relatives in the US are still being requested to submit immigration DNA testing that is done through one of the two accepted Washington labs. This is occurring after the first step of the visa application has been approved and may lawyers are wondering just why.

Immigration DNA testing is no different than any other type of DNA testing. The process used to identify the relationship would be consistent with that which is used when paternity tests are run. A swab on the inside of the cheek in the mouth, or a blood sample - either will work.

But for the immigration department to recognize it the results must be determine at one of the two labs previously mentioned. For further details on their procedure be sure to contact US immigration.

So although immigration DNA testing can be a positive tool it can also be a tool that's abused way too often.

About The Author

By:Morten Hansen

Article Source: dna results


dna molecule

dna molecule
The double helix, which we today associate with the DNA molecule, is a very antique phallic symbol, best recognized in the form of the winged double-helical wand or caduceus, otherwise referred to as the "rod of Hermes." The Caduceus had its origin in the double phallic symbol of Paleolithic antiquity, in association with the office of the Shaman, who, in the traditions of the Fertility Cult, was the boy-consort of the Earth-Mother, inferior to her in status in matriarchal Paleolithic societies. Thus, we find the phallic rod, in historic times, intimately associated with Hermes, the "messenger," in his role as "psychopompos" that is, "guide of souls."

The diverse associations of the shaman, in traditional culture, testify to the broad aspects of the office of the shaman in traditional societies. Besides his function as link between the physical and spiritual realms, he was a native doctor, diviner and general miracle practitioner. The folktales of traditional cultures reveal the cross-cultural awareness of the often significant infusion of quackery and legerdemain trickery into shamanic practice.

In Paleolithic Mediterranean societies, however, the evidence of cave mural art is that the earliest association of the office of the shaman had been with regard to the problem of animal fertility magic; a fact which should be expected given that prehistoric human societies were mostly hunting and gathering cultures. The double phallic symbol was, therefore, a representation of the potency of the spiritualized masculine principle in nature with respect primarily to creative-generative functions: the creative-generative function of cosmic divine prinicple, as it affects animal life, being the issue of primary interest to the animal fertility cult.

Closely associated with the double-helical wand of Hermes is the so-called rod of Asclepius, a shamanic deity of medicine and healing. The use of this symbol by Moses in the wilderness testifies to its antiquity. In contrast to the double-helical rod of Hermes, the Asklepian, as it is also called, consists of a single serpent-helix. Serpents are phallic symbols of divine spirit potency in traditional lore; thus, both the Asklepian and the Hermes rod have the same primary symbolic significance.

The association of wizards and witches with magical staffs or "magic wands" recalls the tradition of the magical creative potency of the helical shamanic staff of office. The English word "wand," in reference to the magical phallic staff of the sorcerer, is derived from a philological root indicating "winding," "wavy," "undulating," or "supple," in reference, of course, to the helix of the Asklepian, and the caduceus. Such English words as "wind," "wend," "wander," and "wonder," are derived from the root of the word "wand."

The coincidence of an antique phallic symbol of God's creative potency with the structure of Deoxy-Ribonucleic acid (DNA) is a remarkable one indeed. It is almost as if God as nature's artificer appended his signature to his biological systems creations as an artist might his painting or sculpture!

By:John Thomas Didymus

Article Source: dna molecule


dna laboratory

dna laboratory
It is better to be safe than sorry. This is what every DNA patron must remember since DNA results are life changing. DNA is considered to be conclusive all the time so there is almost no questions posted after the results are out. Due to this make or break scene, prospective clients must make sure that they are putting their lives at reliable hands. Anyone can claim accurate, convenient and fast results, but not all can really deliver clean and real results. As such, before choosing the most reputable DNA testing lab, one must look into the credentials and accreditations, which speak for the credibility of the company.

The first step is to look for accreditation by the American Association of Blood Banks. This body has already been setting the bar of excellence in parentage testing for over 20 years. Those affiliated with AABB have valid, scientific and safe operations. The review and inspection done by the AABB are intensive so no substandard DNA testing lab can get pass through AABB. Local Health Departments must also approve the operation of the DNA testing center. These bodies ensure the interests and welfare of their people so they are known to conduct rigorous inspections on all laboratories with DNA service. Another accrediting body is the College of American Pathologists. They are recognized worldwide in fostering excellence in the field of pathology and laboratory medicine. As such, they will never risk their name for some petty testing center. The Forensic Quality Services International is another organization that checks for ISO compliance. There may still be other bodies that ensure high quality performance in DNA testing. Usually, accredited laboratories take pride in these credits so they post the seals and logos of the mentioned bodies. When checking the internet, the companies will surely mention these credentials, which say that they are cut above the rest.

Giving into sweet talks and flashy claims of DNA testing lab can be risky and too dangerous. DNA results put a grave responsibility to the perfect match so extra caution must be taken to ensure that justice is given to whom it is due.

By:Lindsey Jenkins

dna analysis

dna analysis

DNA testing has become practically indispensable in any criminal investigation, in order to obtain the absolute proof regarding the identity of the criminal. DNA testing is the best identification tool, and has helped convict or exonerate countless people accused of a crime, can establish paternity with almost 100% accuracy, or identify accident victims who could not be identified by any other means.

Each person has a unique DNA, determined by a small fraction spread throughout the total genome. Unless you have an identical twin, no one else has the same sequence of bases in all of the sections of DNA.

DNA testing is based particularly on these unique sequences, analyzing these specific sections called markers. DNA samples can be taken from cells found in body fluids, skin, hair follicles or the inside of the cheek. After isolating the DNA from the cells, millions of copies are made using an enzyme that speeds DNA reproduction. Then, other reactions break apart the DNA molecules at specific locations in order to isolate particular markers. These markers are ultimately compared to the unknown sample. The more markers identified, the more chances that the match between two samples is accurate. DNA analysts look at a number of different markers to create a "DNA fingerprint".

All methods of collecting DNA samples, be it blood, cheek swab, skin, is equally accurate, because all cells contain the same DNA. So contrary to popular belief, a blood sample is no more accurate than a cheek swab, for example. However, when hair samples are used, the hair must be pulled, not cut, because hair is not made of living cells. If it 's pulled it carries with it some cells from the living follicle.

It is impossible to absolutely identify a person as the source of a DNA sample without looking at the whole of that person 's DNA. With identical twins, it 's never possible, but with many markers the chances for an accurate identification are favorable. Typically, the comparison is made using between 2 and 13 markers. With 13 or close, it 's extremely unlikely that an incorrect identification will occur, however it is not absolutely impossible.

Still, if an absolute match is hardly possible, a mismatch is very easy to identify through DNA analysis. For example, in a criminal investigation a suspect can be easily eliminated as the source of a sample based on the absence of a single marker. All DNA from a particular person must match from one end of each molecule to the other.

DNA testing has consisted a huge breakthrough, and is a strong pillar in any criminal investigation. DNA analysis has even been used to reopen old cases that were considered solved, because DNA samples remain useful for a very long time. The results are far more accurate and reliable than any other form of identification, and numerous people have been cleared for crimes they did not commit based on DNA analysis.

Alexandra is the editor of this article, but she also started a new project about burglar alarm monitoring. This is a website which provides resources about wireless burglar alarms.

By:Alexandra Cazacu

Article Source: dna analysis


dna structure

dna structure
In all that we see in nature, the principle that we usually see is that form follows function. This is because in almost all creatures and plants, the unique features that they have serve a purpose. One example of this includes how some creatures are able to camouflage themselves within their background because their skin color allows them to do so. Other examples include birds with specially shaped beaks to help them catch prey, and the woodpecker is a good example of this. However, this principle does not only apply to the physical attributes of animals and plants as this principle is also followed up to the molecular level. This is seen on how the structure of the most basic genetic molecule, which is DNA also follows this principle.

Form follows function

The function of DNA is for replication and the transfer of genetic information. Given this, it can be expected that the structure of DNA would be designed to serve these functions. For its replication function, the two-strand structure of DNA molecule allows for the separation of these two strands to be able to bind with newly developing DNA molecule. This means that the two strands can "give birth" to a limitless number of DNA molecules as long as the replication process goes on.

For its genetic information transfer function, the way by which DNA molecule is made up of sub-units that contain a sugar, a phosphate group and four nitrogenous bases allows for the molecule to be arranged in a way by which a code is formed. This code is determined by the sequence of the four nitrogenous bases namely, adenosine (A), cytosine (C), thymine (T), and guanine (G). During the replication process, this code is transferred to the new DNA molecules that are formed through a process by which a gene that is formed or coded in the same sequence in which the nitrogenous bases are sequenced in the DNA. These genes then determine the proteins that make up and establish the biological characteristics of an organism.

As with anything in nature, DNA also follows the principle that form follows function. This is because the unique structure of DNA allows it to serve its two main functions, which are the replication and the transfer of genetic information.

By:Kristy Annely

Article Source: dna structure

วันศุกร์ที่ 15 เมษายน พ.ศ. 2554

dna profiling


dna profiling
DNA Profiling and Its Uses in Court

Stronger evidence in courtrooms--it's what every attorney, defendant, and plaintiff dreams of. Beginning in the last 1980s, this is exactly what began to surface through DNA profiling.

In addition to the one-of-a-kind pattern engraved on our fingers, each of us possesses a unique identifier that is built within our bodies. DNA (deoxyribonucleic acid) is the genetic blueprint that determines our biological characteristics. DNA is a long molecule located in almost every cell in the human body. When we are conceived, we inherit half of our DNA from our mother and half from our father. Although every human's DNA is 99.9% identical, the remaining 0.1% is enough to uniquely identify an individual. Our DNA is made up of about 3 billion base pairs, the building blocks of DNA composed mainly of carbon and sugar. The 0.1% (3 million) base pairs that make us unique are what constitute our DNA fingerprint.

Over the past 20 years, courts have been able to rely upon the consistent accuracy of DNA profiling, also known as DNA fingerprinting, to solve crimes. DNA profiling has even been used to solve crimes that are more than 30 years old.

Here's how DNA profiling is done:
# Specimens are collected from the crime scene. Anything can be used to extract DNA: Hair, blood, bodily fluids, etc. In some cases, victims may have scratched their attackers, in which case skin cells can be extracted from underneath the victim's fingernails in order to identify the criminal
# The DNA needs to be isolated and cut so that it can be matched against other samples. Special enzymes recognize patterns in the DNA and cut the strand
# In a process called electrophoresis, the strands are then placed on a gel where they are separated an electric current passed through it.
# The resulting fragments are compared against samples of all suspects and a match is determined.

DNA profiling is mostly used in sexual offences (60%), homicide (20%), assaults (7%), robbery (7%), criminal damage (1%), and other cases (5%).

DNA profiling narrows the list of suspects that authorities need to work through. The FBI commented that DNA profiling allows them to dismiss one-third of rape suspects because the DNA samples do not match. Authorities recognize the possibility of specimens being planted at crime scenes, and therefore continue to investigate the crime based on motive, weapon, testimony, and other clues in order to more accurately solve the case.

Article Source: dna profiling


structure of dna

structure of dna


In all that we see in nature, the principle that we usually see is that form follows function. This is because in almost all creatures and plants, the unique features that they have serve a purpose. One example of this includes how some creatures are able to camouflage themselves within their background because their skin color allows them to do so. Other examples include birds with specially shaped beaks to help them catch prey, and the woodpecker is a good example of this. However, this principle does not only apply to the physical attributes of animals and plants as this principle is also followed up to the molecular level. This is seen on how the structure of the most basic genetic molecule, which is DNA also follows this principle.

Form follows function

The function of DNA is for replication and the transfer of genetic information. Given this, it can be expected that the structure of DNA would be designed to serve these functions. For its replication function, the two-strand structure of DNA molecule allows for the separation of these two strands to be able to bind with newly developing DNA molecule. This means that the two strands can "give birth" to a limitless number of DNA molecules as long as the replication process goes on.

For its genetic information transfer function, the way by which DNA molecule is made up of sub-units that contain a sugar, a phosphate group and four nitrogenous bases allows for the molecule to be arranged in a way by which a code is formed. This code is determined by the sequence of the four nitrogenous bases namely, adenosine (A), cytosine (C), thymine (T), and guanine (G). During the replication process, this code is transferred to the new DNA molecules that are formed through a process by which a gene that is formed or coded in the same sequence in which the nitrogenous bases are sequenced in the DNA. These genes then determine the proteins that make up and establish the biological characteristics of an organism.

As with anything in nature, DNA also follows the principle that form follows function. This is because the unique structure of DNA allows it to serve its two main functions, which are the replication and the transfer of genetic information.

Article Source: structure of dna


dna fingerprinting

dna fingerprinting

DNA Fingerprinting Analysis is also known as DNA profiling. Essentially, a person's DNA is isolated in a sample of bodily fluids like saliva or blood, et cetera, and in other things like hair. Next, specific markers of DNA are located. This analysis is DNA Fingerprinting Analysis. The results of such an analysis are different for every individual, like a fingerprint is. These analyses are used for a number of purposes, including solving crimes, determining biological families, and more. Humans have very similar DNA, as members of the same species, but it is the differences that allow individuals to be identified.

DNA Fingerprinting Analysis is most widely known for helping to solve crime. Over the last few decades, DNA databases have been established to assist law enforcement in identifying perpetrators. When someone commits a crime and leaves behind DNA evidence, such as blood or semen, the police can complete a DNA Fingerprinting Analysis. This information will identify the unique DNA characteristics of the perpetrator. With this information, they can run a person's DNA through a DNA database. If the perpetrator's DNA information is in the database, they can identify them. Another way this type of evidence can help law enforcement is by confirming that a suspect is indeed the perpetrator. If DNA evidence is left behind, the police can compare the DNA profile to a suspect. If it matches, it can help police confirm that the suspect is the perpetrator.

Surging in popularity in recent years is the use of DNA Fingerprinting Analysis to determine parentage. Adopted children have sought out potential birth parents and taken DNA tests. Or, children who are unsure of their father's identity will seek out a potential father and take a DNA test. All people involved in the DNA test offer a DNA sample, which is usually saliva but is sometimes blood. Then, a company compares the DNA, and informs the client if there is a match or not. As so many people require these services, the cost of such DNA Analysis is much less than it once was.

Many people are interested in using DNA Fingerprinting Analysis to confirm paternity or other relatives. In fact, in popular culture, such profiling is often televised on various talk shows. At times, the validity of such tests have been questioned. A person should carefully research options and results before deciding to move forward. The use of DNA Fingerprinting Analysis has also been popularized on the plethora of crime shows being televised on network and cable television. With such vast recognition in popular culture, the surge in popularity is easily explained.

There are a number of possible applications for DNA Fingerprinting Analysis. Popular culture has illustrated how DNA Fingerprinting Analysis can be applied, and increased its popularity. Such advanced science does not often become a part of everyday vernacular, and people are becoming more involved in the possibilities than ever before. Either by solving crimes or finding families, DNA profiling is the wave of the future.

Article Source: dna fingerprinting


dna models

dna models

Besides knowing what DNA stands for - which means "Deoxyribonucleic Acid", there are few things that we might have overlooked. The discovery of DNA model has lead many scientists in encrypting codes of life which could bring us closer to humanity and self-assurance.

DNA replicates in cells when the environment permits them to do so. During DNA replication, new strand of DNA will be duplicated based on the DNA template which acts as a mould. The new DNA strand elongates in which the nucleotides are attached to each other based on sequences of the DNA template. It is like a building-blocks model, it has different color blocks and you use these color blocks to build a tower or a building.

What personal insights that we gain into the discovery of DNA?

In order to start a task, or a project, it must begin with building a foundation. Building a foundation must be based on proper sequences. Similarly in DNA replication process, it begins with a DNA template that allows nucleotides bind at it with joining one nucleotide at a time.

At the same time, a chemical bond is formed among nucleotides which also produce the backbone structure for the newly-formed strand DNA. Things would become awry when you started a project with weak foundation - it like having a sand foundation; things will crumble easily even though you are just getting started.

The newly formed DNA strand eventually matures and become one DNA template in the next DNA replication. It is like a life-cycle - what comes around goes around. Basically, building a foundation is an on-going process; it stops when it is done.

The nucleotides are subsequently joined together by grouping one nucleotide at a time. Creating a product reires sequences. Simple small steps should be taken before making a product. Each small step is crucial in such a way to define our objectives or goals that is essential to our success.

As a matter of fact, we learn to sequence things since young and it has proven that our focuses on life can be maintained as we reached different stages of life.

In the blooming of DNA technology era, DNA testing has been introduced to various fields that have increase popularity of the noble DNA structure which has celebrated 50 years of its discovery. DNA testing has raised humanity issues such as tracking down our ancestor lines. As we know that our DNA contains genes that inherited by our parents, it is possible that we can have track down our ancestors based on modern DNA testing procedures.

DNA is a unique structure that stores millions of information about inheritance. Some of this information is passed from one generation to the other. Ancestor search show us about our existence, and how we are connected to each other.

Each of us has an identity - it means that we have our own distinctive DNA fingerprint. Our DNA fingerprint is like our entity - it is private and protected according to civil rights. There is nothing to be ashamed of being different than others.

Knowing our existence helps us to understand ourselves better including pin-pointing our strengths and weaknesses. These could improve your ability to communicate with people especially in broadening social networking.

There had been several cases about exoneration of wrongfully imprisoned convicts over the past few years. It takes perseverance and patience for them to find new taste of life. DNA testing has given them fresh of life and brought justice back to them. People have gain insight into the plight of the innocent prisoners, as they have begun appreciating the values of life. It has taught us to be firm at making decisions and be brave to make a stand against criticisms.

By:J.J. Yong

Article Source: dna models

dna

dna


DNA testing is done for many different reasons. DNA evidence can link an alleged criminal to a crime scene. DNA paternity and maternity testing can identify a child's father or mother. DNA relationship testing can determine if two individuals are full or half siblings. DNA ancestry testing can determine ethnic origins and genealogical roots.

How DNA testing is done depends on the results desired and the samples available. DNA fingerprinting (or profiling as it's also known) is the process of analyzing and comparing two DNA samples. Only identical twins have the exact same DNA sequence, everyone else's DNA is unique. This makes DNA the perfect way to link individuals to each other or to locations where they have been.

The entire DNA chain is incredibly long, much to long to examine all of it. Human DNA is made up of about 3.3 billion base pairs. The differences between DNA samples occur only in small segments of the DNA--the rest of the DNA is pretty much the same. DNA testing focuses on those segments that are known to differ from person to person.

As DNA testing has evolved over time, the testing methods have become more precise and are able to work with much smaller DNA samples. Early DNA testing was done using dime-size drops of blood. Today's tests can extract DNA from the back of a licked stamp. The DNA must be extracted from whatever sample is provided. DNA must be isolated and purified before it can be compared. In essence, it has to be "unlocked" from the cell in which it exists. The cell walls are usually dissolved with a detergent. Proteins in the cell are digested by enzymes. After this process, the DNA is purified, concentrated, and tested.

DNA testing is done most often today using a process called "short tandem repeats," or STR. Human DNA has several regions of repeated sequences. These regions are found in the same place on the DNA chain, but the repeated sequences are different for each individual. The "short" tandem repeats (repeated sequences of two to five base pairs in length) have been proven to provide excellent DNA profiling results. STR is highly accurate--the chance of misidentification being one in several billion.

By:Alex Blake

Article Source: dna