Human genetics and human rights. Identifying the families of kidnapped children.

Between 1975 and 1983 in Argentina, at least 145 children were kidnapped with their parents or born in captivity to imprisoned women and then separated from their mothers. The parents of these children generally remain among the missing persons. However, the grandparents of the kidnapping victims and the Argentinian government are concerned with identifying these children. Genetic analysis can aid in determining whether a child who may be among the kidnap victims is related biologically to a particular family. Laboratory analysis of genetic markers in human blood enables the calculation of an "index of grandpaternity." This index reflects the probability that a child shares genes with a specified set of grandparents because he is their grandchild compared to the probability he and they share similar genes only by chance. The most useful system for this analysis is HLA, although other genetic markers including blood groups, red cell enzymes, plasma proteins, and DNA polymorphisms can be tested to provide adequate information in families with only one or two living grandparents. This approach has been applied successfully in Argentina, with an index of grandpaternity for one family of 99.9%, based on HLA typing only.