Biostatistics for mixed stains: the case of tested relatives of a non-tested suspect

Analysis of a mixed biological stain by means of highly polymorphic VNTR sy stems usually reveals a profit composed of multiple markers. If the victim and one or several suspects match the profile, the evidential strength of t he matches has to be very carefully analysed. The appropriate methods for t he statistical analysis of DNA profiles advanced recently were limited to c ases with no relationship between the tested and non-tested persons. The pr esent paper extends the theory beyond this limitation.