Allowing for within-subpopulation inbreeding in forensic match probabilities

The importance of allowing for recent shared ancestry when calculating forensic match probabilities has been recognised for some time. Within-subpopulation inbreeding will also affect the match probability, and ignoring these effects can lead to an overstatement of the strength of the DNA evidence against a defendant. However, inbreeding can be readily accounted for in match probabilities by incorporating the inbreeding coefficient F-IS into calculations. We derive the necessary formulae, and demonstrate the effect of including F-IS (in addition to F-ST) in the equations. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.