Genomic DNA was extracted using a rapid non-enzymatic method (1). The PCR primers and the parameters for PCR amplification of all the five Y-chromosomal STRs were as described by Kayser et al. (2) and de Knijff et al. (3). The forward primer of each locus was labeled with flourescent CY5^™ dye amidite (Amersham Pharmacia Biotech) and PCR was carried out in a Hybaid^™ thermal cycler using Taq polymerase (Roche Molecular Biochemicals). Amplimers were electrophoresed in 6% denaturing urea gel (7M) and analyzed by fragment manager using ALF Express DNA Sequencer (Amersham Pharmacia Biotech). Internal ladders were used for the accurate size determination. Allelic ladders were prepared for each locus and used as external standards in addition to CY5^™ labelled 50 to 500 bp DNA ladder (Amersham Pharmacia Biotech). At each locus, the amplimers were compared with the standards, kindly supplied by Dr. Chris Tyler-Smith from Oxford University, Oxford, UK, for confirmation.