Beaudet wrote in the letter that "clinicians uncovering a likely incestuous relationship may be legally required to report it to child protection services and, potentially, law enforcement officials" since the pregnancy might have occurred "in the setting of sexual abuse." The letter was prompted by a Baylor laboratory's discoveries that developmental disorders in a number of pediatric patients were caused by incestuous relations not previously disclosed to doctors. The testing is done to find the disorder's genetic basis, typically involving mutations, deletions or duplications. But large blocks of identical DNA are evidence the child's parentage involved first-degree relatives.
If you're curious if you are the product of incest, David Pike's runs of homozygosity (ROH) detector (Mozilla only) might be useful if you have a genotype file. Sometimes I wonder if mass technology is going to come to fruition far earlier than it takes to write up editorials and publish them. Of course even people who are not the product of first-degree incest can have very long ROH. Look at Zack (though is in part a legacy of the consanguineous marriage practices common in his parents' community). And there will be many people who are going to get their siblings typed (as I did), so amongst the intelligent set cuckoldry, rare as it is, will be exposed.