Sequence variation of a variable short tandem repeat at the D18S535 locus

A short tandem repeat in the D18S535 locus was sequenced in 25 selected alleles. A total of 8 different alleles were found which can be designated according to the total number of repeats. This STR is a simple hypervariable STR consisting of blocks of (GATA) repeats with a basic sequence structure (GATA)1(GACA)1(GATA)1 (GAT)1(GATA)9-16. Population data showed that this is a highly polymorphic STR with a heterozygosity of more than 0.80, a simple structure and small size (130-158 bp) which makes this an interesting DNA polymorphism for forensic and genetic purposes.