Chimerism: The DNA Monster

Unless you've been asleep the last 20 years, you should be familiar with the term DNA--Deoxyribonucleic acid. Thanks to highly publicized trials such as O. J. Simpson's and Scott Peterson's, most people know DNA is the genetic fingerprint that's been used to --

• Determine if two people are related
• Used as proof in criminal trials
• Prove paternity
• Test for genetic diseases

It has become accepted around the world that DNA, collected under the proper conditions, is infallible proof that identifies an individual by his or her unique genetic fingerpint. It has been used in death penalty cases, paternity cases, and to make medical decisions. It is infallible. . . Really?

Consider the case of Lydia Fairchild whose story was recently featured in a documentary. When this young single mother applied for assistance, she was required to prove paternity of her children. Oddly, the tests proved that while her boyfriend was the father, she had no genetic link to her children. This was the beginning of a legal odyssey in which she almost lost custody of her children. The state alleged she was involved in a surrogacy scam. Fortunately, another test proved that her children were genetically related to her brother. This oddity resulted in further testing. Eventually Lydia was proven to be a chimera--she carried two types of DNA.

The term chimera is taken from the mythological monster made up of a lion's head, a goat's body, and a snake tail. The condition is believed to occur when two fraternal embryos combine in the early stages of development. A person with this condition can have teeth that contain one type of DNA and saliva that contains another. It is not known how many people have this condition, but it is easy to extrapolate the consequences. How many parents have been denied parental rights because a DNA test showed them to have no genetic link to a child? How many people have committed crimes and gone free because their DNA did not match that found at the crime scene?

Your medical issues may not be as serious, but keep in mind that DNA is not the final arbiter.

? 2006, Clara Myers. Visit Privy Test for paternity test kits. Privy Test at http://privy-test.com offers many at-home test kits for diseases and environmental toxins.