QI am writing a screenplay in which an infant is kidnapped a month after birth. Seven years later the police find a seven-year-old boy dead. They suspect it is the missing infant from seven years prior. The mother died in childbirth. There are no dental records. How would they identify the child?
RG
Chicago, Illinois
AIdentifying an unknown corpse is often very difficult. As you pointed out, there would be no dental records since the child disappeared as an infant before he had teeth much less dental records. With the mother gone, there would be no direct way to get DNA from her. Her corpse could of course be exhumed, but even if this isn’t possible, all is not lost.
The fact that the police believe they know who the dead child is helps immensely. Rather than simply having a John Doe corpse, a strong suspicion as to his identity guides their investigation and points them in the right direction.
The only sure way of proving paternity, and in this case proving that this child belonged to the mother in question, would be to have DNA from both the mother and the father. If the father is known, obtaining his DNA is possible, and of course DNA could be taken from the child’s corpse.
Getting the mother’s DNA could be more problematic but not impossible. Perhaps someone had an old hairbrush or toothbrush that belonged to her. Maybe she had sent letters to friends and relatives and in doing so had licked the envelope and the stamp. DNA can often be obtained from these items even after many years. If DNA is acquired from the child, the father, and the mother, then it can be proven with certainty that the child was the offspring of these two parents.
There are other options. Mitochondrial DNA (mtDNA) is passed down the maternal line generation after generation essentially unchanged for many thousands of years. This means that the child would have the same mtDNA as any of his siblings (if there were any), the mother, the maternal grandmother, and any maternal aunts. The finding that the mtDNA of this child matched mtDNA from a known child of the mother (a sibling of the dead child), from the mother herself, from the grandmother, or from a maternal aunt would be strong evidence that this child was indeed a child of the dead mother. Who else could it be? This is not as absolute as using nuclear DNA, but it is powerful evidence since not that many children are abducted and their bodies found seven years later.
Since your child is male, there is another option. If the father was known and DNA was obtained from him, it could be matched to the child using Y chromosomal DNA. It’s similar to mitochondrial except that it is found solely on the Y chromosome and is passed down the paternal line. This child would have the same Y chromosomal DNA as his father, his grandfather, any male siblings, and any paternal uncles.
One or more of these methods could be employed to identify your unfortunate child.