Sequence variation of two hypervariable short tandem repeats at the D22S683 and D6S477 loci

For two short tandem repeats at the D22S683 and D6S477 loci, 30 and 22 selected alleles, respectively were sequenced. A total of 20 different alleles were found for the D22S683 locus and 12 alleles for the D6S477 locus. In both systems the alleles were designated according to the total number of repeats. D22S683 is a hypervariable STR consisting of blocks of (TATC) repeats with a basic sequence structure (TATATC)n (TATC)n (ATC)0-1 (TATC)n. The D6S477 locus consists of blocks of (TCTA) repeats with a basic sequence structure (TCTA)n (TA)1 (TCTA)0-2 (TA)0-1 (TCTA)n. Population data showed a heterozygosity of 0.89 for D22S683 and 0.75 for D6S477. These STRs are promising markers for forensic genetics as they are robust and can be easily included in multiplexes.