Five Y chromoson~al STRs (DYS19, DYS3891, DYS38911, DYS391, and DYS393) were investigated from 64 ran- dom. normal, and healthy male volunteers in two distinct population groups (Ezhavas and Muslims) of the Kerala state in South India. Ezhavas belong to the Hindu religious fold whereas Muslims are a religio-ethnic group. Both groups speak Malayalam, an Indo-Dra- vidian language. DNA was extracted by using a non-enzymatic method (1). PCR amplification of all the fibe Y STR loci (DYS19, DYS3891, DYS38911, DYS391, and DYS393) was achieved by using locus specific primers and the PCR conditions were as described by Kayser et al. (2) and de Knjiff et al. (3) Forward primer of each lo- cus was labeled with fluorescent Cy5^TM dye amidite (Amersham Pharmacia Biotech Pvt. Ltd. Sweden). A final volume of 25 μL PCR reaction mixture containing 25ng of genomic DNA was car- ried out in HybaidTh[ thermocycler. PCR amplicons were elec- trophoresed in 6% (wlv acrjlamidelbis-acrylainide) denaturing high-performance sequencing gels (ready-mix. ALF grade. Amer- sham Pharmacia Biotech) using ALF Express DNA sequencer (Amersham Pharmacia Biotech). External size standard (50-500 bps) was used in every 8th lane and internal ladders were used in each lane of the gel. The DNA standards lundly supplied by Dr. Chris Tyler-Smith were used for the confirmation of the allele sizes of each locus.