General Formulas for Calculating Commonly Used Kinship Index

Abstract

Objective To derive general formulas for calculating commonly used kinship index （KI）. Methods By introducing the Kronecker symbol， the formulas used to calculate the same KI under different genotype combinations were summarized into a unified expression. Results The general formulas were successfully derived for KI in various case situations， including the paternity index， full sibling index， half sibling index， avuncular index， grandpaternity index， first-cousin index， and second-cousin index between two individuals without or with the mother being involved; grandpaternity index between grandparents and a grandchild without or with the mother being involved; half sibling index between two children with two mothers being involved; full sibling index among three children; and half sibling index among three children with no， one， or two mothers being involved. Conclusion The general formulas given in this study simplify the calculation of KIs and facilitate fast and accurate calculation through programming.

Keywords

• |forensic genetics|formula|kinship index|kinship testing|paternity index|kronecker symbol