What does DNA stand for?

DNA stands for DeoxyriboNucleic Acid, the “substance” that is analyzed in the state-of-the-art test to determine paternity, and in other cases, maternity. The genetic information or “genetic code” of a person is carried in the DNA of the chromosomes and mitochondria. An individual’s genetic composition is called genome and is established at conception. We have 100,000 genes encoded by 3 billion chemical pairs in our DNA. Each person is, indeed, an individual, with a unique genome.

How accurate is DNA testing ?

Like fingerprints, DNA is very accurate. If nine ministrands of DNA coding match the suspect’s, odds are billion to 1 that the suspect is “the one.” The test is useful not only in determining paternity but in murder, rape and other cases. In the news all over the world not too long ago was the semen stain on Monica Lewinsky’s dress which matched the DNA from a blood sample taken from President Clinton, which discovery ultimately forced him to admit his famous “inappropriate relations” with Monica.

When was DNA fingerprinting developed?

DNA was discovered in 1953. In 1984, Alec Jeffreys of the University of Leicester in Britain invented “genetic fingerprinting” to identify individuals, using unique sequences of DNA. It was a year later when this test was first used in a criminal investigation. The National Center for Human Genome Research of the United States was created to oversee the 3-billion dollar project to map and sequence all human DNA by year 2005. In 1990, the formal launching of the International Human Genome Project was done. Two years later, the U.S. Army started collecting blood and tissue samples from all new recruits as a part of a “genetic dog tag” program to better identify soldiers killed in combat.

How far along is the technology?

In the Fall of 1998, the power of DNA technology catapulted exponentially when the US Federal Bureau of Investigation activated its new Combined DNA Index System, a database that contained gene prints of 250,000 convicted felons and 4,600 DNA samples left at the crime scene of unresolved cases. In England, where genetic databases were in operation since 1995, suspects are routinely screened in this manner, and they have more than 360,000 gene prints online. Police remove the profile from the record when the suspect is cleared. Each week in Britain 500 matches are made between specimen taken at crime scenes and the database entries, and police claims a 70% success rate in cracking crimes. In the United States, more than 200 outstanding cases have been solved by DNA typing.

How does DNA benefit the convicted person?

DNA testing does not help only the people investigating crimes, but also the “innocent” but convicted persons. At least 75-death row inmates in the United States have been saved from execution when their convictions were overturned. Ten of these reversals came on the basis of new DNA evidence. DNA typing was partly responsible for the increase in the number of fathers acknowledging paternity to triple from 512,000 in 1992 to 1.5 million in 1998. In about a third of welfare cases and another 10% of other cases, it was conclusively proven that the man named by the mother (who was asking for financial support) turned out not to be the biological father.

What is store for DNA testing?

The use of DNA fingerprinting is limited only by the imagination. It is now predicted that within a decade investigators may be able to use DNA information to draw a sort of genetic police sketch of a suspect’s appearance, including race, facial shape, build, etc. and expedite the conviction of criminals.

How long does the DNA specimen last?

Accurate DNA testing has been done on mummies in ancient Egyptian tombs. Last year, DNA testing proved that US President Thomas Jefferson had a child with one of his slaves, Sally Hemings, settling an age-old historical dispute. Obviously, the specimen lasts “forever.”

How is the specimen collected for DNA testing?

Taking blood samples used to be the only method of collecting specimen for DNA typing. Today, obtaining the specimen (smear) from a buccal (inner cheek, mouth) swab has been found to be as accurate as blood. Public commercial DNA-typing laboratories all over the world use this simple buccal swab method, although blood is still being used in some centers.

How much does each test cost?

Commercial Laboratories in the United States charge about $450 to $600 per

DNA typing, and the result is ready in 2-3 weeks. For an added fee, the result could be obtained within 72 hours. In the past 10 years, DNA-based paternity testing has more than tripled to about 247,000 cases.

In what other situations has DNA typing helped?

In resolving inheritance disputes, babies switched in maternity wards, determining recent or historical claims on ancestry or lineage, identification of human remains, resolving criminal cases, etc.

After a negative DNA paternity test, then what?

Heart breaking stories associated with DNA testing are common. One such account was that of a recently divorced man, who, after 15 years, found out through DNA typing that the teenage son he thought was his was actually not fathered by him. He broke down and cried. Later, after he regained his composure, he told his lawyer “I cannot throw this boy out of my life on account of a laboratory test result. I have loved and cared for him for 14 years as a father, and DNA typing cannot and will not change all that.” Indeed, parenthood is more than just a biological linkage of sperm fertilizing an ovum or a womb carrying the fetus. It is the selfless love and unceasing moments of caring over time that makes a man a father and a woman a mother. The great advances in science and medical technology, as always, should be tempered with good ethics and moral values, justice, compassion, and above all, love and wisdom.

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Philip S. Chua, MD, FACS, FPCS, Cardiac Surgeon Emeritus in Northwest Indiana and chairman of cardiac surgery from 1997 to 2010 at Cebu Doctors University Hospital, where he holds the title of Physician Emeritus in Surgery, is based in Las Vegas, Nevada. He is a Fellow of the American College of Surgeons, the Philippine College of Surgeons, and the Denton A. Cooley Cardiovascular Surgical Society. He is the chairman of the Filipino United Network – USA,  a 501(c)(3) humanitarian foundation in the United States. Email: [email protected]

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