She was something rarer than a miracle. What they discovered in her ovaries will blow your mind | HO

“It was very disturbing to try and make sense of whatever was going on with this,” Karen recalled. “I knew that there had to be a scientific answer to why the DNA didn’t match.”

Karen needed an urgent kidney transplant a decade ago. She, her husband, and her two eldest sons had blood tests to look for a donor match. The results when they came back were shocking. The DNA of her children did not match her. The hospital had never seen a case where a mother did not match her children’s DNA.

“I really just couldn’t understand why on earth this had happened,” Karen said. “I knew that then that the hospital had made a very bad mistake.”

Her sons were told the news carefully. “My mom and dad brought us over and said, ‘Well, we got something to tell you. They’re telling us that you’re not our children,'” one son recalled. The family’s reaction was concern for their mother’s health, not doubt about their relationship.

Karen’s third son was tested for the first time during this period. He matched her. The mystery deepened.

The doctors at Beth Israel Deaconess Medical Center consulted colleagues for an explanation. The initial responses were skeptical. One suggested Karen might have had in vitro fertilization and wasn’t admitting it. Another hinted that something was amiss within the family.

But Karen’s primary care physician, Dr. Lynne Uhl, knew her patient well. “On a personal level, it didn’t enter into my mind because I had a well-established personal relationship with this individual and was confident just based on conversations that she in fact was the mother of these two sons.”

One response mentioned a remote possibility: chimerism. The condition is extremely rare, with fewer than 40 possible cases documented worldwide. Chimeras have two completely different genetic identities inside their bodies, created from separate sets of DNA. The doctors picked up on this lead and decided to pursue it.

Chimerism occurs when two fertilized eggs fuse very early in development. Each egg has its own distinct DNA. The fusion incorporates both sets into one embryo. If the embryos are male and female, the resulting person can be a hermaphrodite. If they are the same sex, the person may appear completely normal externally while carrying two genetic identities internally.

In Texas four years ago, surgeon Linda Baker treated a chimeric child who showed visible signs. The baby had unusual skin pigmentation with a line dividing light and dark skin down his belly. Internally, he had both male and female reproductive organs. The blood test revealed chromosomes from both a male and a female.

Karen Keegan showed none of these external symptoms. Finding proof of chimerism in her body would require painstaking detective work.

Meanwhile, Lydia’s situation was becoming desperate. She was called for three interrogations by prosecutors. At the third, they threatened her with a lie detector test. She agreed to take it. Then she received a summons to court.

“Every day I feel like that was going to be the last day I see them,” Lydia said. She kept a diary documenting everything she went through emotionally and physically. When someone would pull up to her house, she would get scared and tell the children not to open the door.

Her mother watched the toll it took. “She was trying to be so positive for her kids to show them that she’s strong and she’s going to make it through this and that everything’s going to be okay. But it was so stressful.”

Lydia called every lawyer in the phone book. None would take her case. They told her there was no way to win against DNA evidence. She went to court alone, facing the state with nothing but her word against scientific proof.

The prosecutor’s first words were that they wanted to put the children in separate guardianships. The judge agreed based on the existing evidence that Lydia was not the biological mother. Guardians were appointed to monitor the children’s welfare while investigations continued.

Lydia’s father, serving time in Montana for a business scam, heard the news from his wife. “It was a startling bit of news to hear. I couldn’t believe that she was even saying that. I felt that they were making Lydia pay for it.”

Jamie Townsend was also interrogated. Prosecutors suggested he might have had children with one of Lydia’s sisters and they were running a welfare fraud scheme together. Jamie insisted he was there for the births. He had seen the babies born. It didn’t matter.

The medical records showing the children’s births, complete with footprints taken in the delivery room, seemed to carry no weight against DNA technology. “All of a sudden they just didn’t want to hear anything else,” Lydia’s attorney later noted.

Lydia was heavily pregnant with her third child as the court date approached. The judge ordered someone to witness the birth and take blood samples from mother and baby immediately. A lab person came into the delivery room, watched Lydia give birth, took blood from the newborn, and swabbed Lydia.

The two-week wait for results was agonizing. “Even after giving birth, you bring your newborn home, you’re happy. I went home still scared because this was still going on. Still scared that they can come any minute and take my kids.”

When the results came back, they showed the same anomaly. According to DNA, Lydia was not the mother of her newborn son. For the family, this was what they wanted to hear. It confirmed that the tests were consistently producing the same impossible result.

Lydia finally found a lawyer, Alan Tindell, who agreed to take her case. He knew she might face serious accusations. “The other question that had gone through the prosecutor’s minds was whether or not she was involved in being a surrogate mother. Is it possible that she’s engaged in some sort of criminal activity? Or maybe she’s even abducted these children from someone?”

By an extraordinary stroke of luck, the deputy prosecutor handling Lydia’s case stumbled across an article in the New England Journal of Medicine. It was written by Karen Keegan’s doctors, documenting their breakthrough in solving her DNA mystery.

After years of investigation, the Boston team had found proof that Karen was a chimera. They tested her thyroid tissue from a prior surgery and discovered a second set of DNA. Some of her hairs carried one genetic profile, other hairs carried another. Her thyroid carried different genetic information than her blood.

“There’s two genetic information,” the lead scientist explained. “It’s almost like because we should inherit half from the parents, she inherit 100 percent from both. It’s almost like a two individual. Karen Keegan is two people in one.”

The fusion that created Karen happened within the first four days after conception. Any later, and she would have been born as Siamese twins. Because both embryos were female, she developed as a normal-appearing woman with no idea she carried two genetic identities.

With this new understanding, the Boston team agreed to investigate Lydia’s DNA. The first tests on her blood showed no evidence of chimerism. But they had learned from Karen’s case that blood testing was only the first step. They would need tissue samples from other parts of her body.

Time was running out. Lydia had to return to court. The scientists hadn’t finished their tests, but they could show something crucial: a definite DNA link between Lydia’s children and Lydia’s own mother. Just as with Karen Keegan, the DNA was present in the larger family. Combined with medical records of Lydia’s deliveries, this was submitted as proof that she was the true mother.

The judge, who had initially questioned whether Lydia was the mother, admitted he had been wrong. For over a year, Lydia had lived with the fear that her children would be taken away.

“I just felt like when he said that, my stomach just dropped and I just felt like I came that close to losing my kids and I just started bawling in court,” she said.

The court concluded that Lydia was the real mother. Jamie Townsend was legally recognized as the father, 16 months after the first DNA results had come in.

The case raised profound questions about the reliability of DNA testing in the legal system. Lydia’s attorney noted the implications. “The courts rely on these tests to a great degree. People go to death row because of DNA tests. People are released from death row because of DNA tests. We’re dealing with the same sort of science.”

The judge who handled Lydia’s case had openly wondered how many fathers he had sent away based on DNA tests that might have been wrong. “What if I was wrong? What if one of these fathers maybe had that same disease?”

Karen Keegan reflected on the broader significance of her case. “I willingly and interestingly participated in all of that research because from my point of view it had an awful lot to do with the way the justice system is moving in our country and the fact that DNA is becoming such an important part of the legal aspects.”

Scientists continue to investigate Lydia’s case. She has provided cheek swabs, hair, blood, urine, and a cervical smear. Significantly, two sets of DNA have been detected in the cervical tissue. But she is now pregnant with her fourth child, which complicates the analysis. The doctors are hesitant to make a full diagnosis of chimerism, though it seems likely.

“I don’t think of myself as a freak,” Lydia said. “I don’t think that I’m like this weird person or whatever ’cause I’m still a person. I still have different personalities. I’m still a normal person and it’s just that there’s something wrong with the DNA.”

Karen Keegan’s doctors believe there may be many more chimeras living normal lives without ever knowing it. “If you don’t come to attention because of a medical need and you look like a normal male or a normal female, you could have a very normal life and never come to anybody’s attention,” one scientist noted.

Karen agreed. “Both my husband and I have always said that there are probably many, many more of us chimeras out there and we just haven’t had a reason to find out about them.”

For Lydia, the experience has left lasting scars. “It feels more scared more than anything. Like what is this and why me? I really want to know more about it to really get to know what this really is and how it came about.”

She continues to work with the Boston scientists, hoping for answers. But regardless of what the final tests show, one truth remains: Lydia Fairchild is the mother of her children. Science eventually proved what she knew in her bones all along.