Highly polymorphic tetramer repeat (GATA)n on human chromosome 11p15.3.

A tetrameric repeat sequence (GATA)n was identified by random DNA sequencing of chromosome 11-specific cosmid clones and located at 11p15.3 by fluorescence in situ hybridization. Oligonucleotide primers flanking the repetitive unit were used to amplify the DNA using the polymerase chain reaction (PCR) and this repetitive element was shown to be highly polymorphic and inherited in typical Mendelian fashion. Analysis of amplification products containing the repetitive element from 45 unrelated Caucasian individuals and five families showed at least five alleles at this locus, ranging from 227 to 249 bases in length. This polymorphism may serve as a useful PCR-detectable genetic marker for 11p15.3, a landmark for disease gene isolation, and a locus for identity testing.