SYMBOLIC KINSHIP PROGRAM

This paper discusses a computerized algorithm to derive the formula fo r the likelihood ratio for a kinship problem with any arbitrarily defi ned relationships based on genetic evidence. The ordinary paternity ca se with the familiar likelihood formula 1/2q is the commonest example. More generally, any miscellaneous collection of people can be genetic ally tested to help settle some argument about how they are related, w hat one might call a ''kinship'' case. Examples that geneticists and D NA identification laboratories run into include sibship, incest, twin, inheritance, motherless, and corpse identification cases. The strengt h of the genetic evidence is always described by a likelihood ratio. T he general method is described by which the computer program finds the formulas appropriate to these various situations. The benefits and th e interest of the program are discussed using many examples, including analyses that have previously been published, some practical problems , and simple and useful rules for dealing with scenarios in which ance stral or fraternal types substitute for those of the alleged father.