X-chromosomal polymorphism data for the ethnic minority of Polish Tatars and the religious minority of Old Believers residing in northeastern Poland.

Population samples of 420 unrelated individuals of the ethnic minority of Polish Tatars and the religious minority of Old Believers residing in northeastern Poland were tested for four X-chromosomal STR frequencies by multiplex PCR and subsequent automated fluorescent detection (ABI 310) using a commercially available kit Mentype Argus X-UL. Kinship tests revealed a typical X-linked inheritance with no mutation. Significant differences in allele frequency distributions confirm previous findings regarding genetic variation among ethnic groups residing in northeastern Poland.