One Person Can Have Two DNA Types? Chimera Said To ‘Undermine’ Up To ‘1 In 8’ DNA Cases In United States

DNA forensic analysis has long been hailed as a “gold standard” in legal cases when attempting to connect a person with a crime scene or object, such as a murder weapon, as reported by Endeavour. It is also seen as the final word in cases seeking to establish the paternity of children or identifying an unknown deceased person.

New revelations about the existence of chimeras in the population of the United States and the rest of the world have cast doubt on cases that make use of DNA in exonerating or eliminating suspects of crimes as well as identifying parentage and the identities of unknowns.

Reportedly, no one knows just how prevalent chimerism is. Estimates range from one in 2,400 to 50 to 70 percent of the population.

DNA is so highly regarded that lawyers and doctors, when presented with evidence that contradicts the forensic validity of a DNA test ruling out a person as a perpetrator of crime or as a parent, would assume the person was guilty or lying, as was the case with Lydia Fairchild, who was told that DNA tests excluded her from being her children’s mother. At first, no lawyer in the United States would take her case, reports the Daily Beast.

Later, after she found a lawyer who would listen, it was learned that Fairchild is a chimera: her body produces two distinct types of DNA.

Recently, a couple was shocked to learn that DNA analysis showed that their child was fathered by the true father’s biological brother. It turns out that the father is a chimera. He absorbed his brother’s fetus in his mother’s womb and now produces his DNA, as reported by the Inquisitr.

Two books have addressed how the existence and understanding of chimeras radically alters how DNA evidence should be viewed: Genetic Justice by Sheldon Krimsky and Tania Simoncelli, listed with Google Books, and Inside the Cell: The Dark Side of Forensic DNA by Erin Murphy, listed with Amazon.

In Genetic Justice, the authors state that chimerism may be as prevalent as “1 in 8” to “1 in 10 to 1 in 2,400.” At the upper end of estimates, figures imply that 12.5 percent of the population may produce two types of DNA. The Daily Beast cites sources that claim “50 to 70 percent” of the population may produce two types of DNA, which seems almost unbelievable.

“The possibility that chimeras are the rule rather than the rare exception could undermine the very basis of the forensic DNA system.”

Since DNA evidence was first considered in criminal cases in 1989, 333 people have been exonerated in the United States of crimes for which they had been seemingly wrongfully convicted based on DNA findings, according to the Innocence Project.

Using a middle-of-the-road estimate of 12.5 percent of the population exhibiting chimerism would mean that about 42 of those 333 people exonerated may actually be guilty. It also means that for justice to be served, each and every case would need to be reexamined, taking these new findings about chimerism into account.

However, this is just tip the of the iceberg. Investigators with police agencies, the FBI, and many other law enforcement agencies routinely investigate crimes under the assumption that DNA evidence is infallible and that a person can only shed one type of DNA. The number of cases that would require reexamination would be unknowable. Possibly in the hundreds of thousands or millions.

Further, there would be many instances where the body of a missing person was ruled out because they were a chimera and DNA taken from two different parts of their body was compared. Innocent people who have been wrongly convicted could be cleared if the true perpetrator is a chimera and had been previously cleared because investigators compared DNA samples originating from different parts of their body.

There is also likely many children and parents who have been denied knowing each other if the parent was a chimera and incorrectly ruled out. There is probably literally seething masses of mothers who have lost all faith in humanity and science upon being told that the only man they slept with couldn’t possibly be their child’s father — because science said so.

There may be many guilty people walking free in the United States. There are likely wrongfully convicted people as well. The exact prevalence of chimerism is still not understood, but it would seem that understanding this newfound aspect of human biology would be of paramount importance to the administration of justice not only in the United States but around the world.

[Photo by Mario Tama/Getty Images]