Independence of VNTR alleles defined as floating bins

Data bases of VNTR fragments determined for Caucasians and blacks by Cellmark Diagnostics and Lifecodes Corporation are analyzed for independence of variants within and between loci. Floating bins are constructed around specific fragment lengths and are used to define discrete genotypes. Simple chi 2 test statistics for independence of bins within and between loci are described and applied to large sets of randomly generated four-locus profiles. The proportions of significant test statistics were about as expected under the hypotheses of independence, suggesting the absence of both Hardy-Weinberg and linkage disequilibrium. In any particular forensic application, however, these tests need to be performed on the fragments in question.