Digital DNA typing at a second hypervariable locus by minisatellite variant repeat mapping

Abstract

Minisatellite variant repeat unit mapping by PCR (MVR-PCR) assays the interspersion pattern of variant repeat units along minisatellite alleles. Mapping such internal variation in the highly polymorphic minisatellite MS31A (locus D7S21), reveals extreme levels of allelic variability, far in excess of that detectable by allele length analysis. Flanking base substitutional polymorphisms have enabled the 5' structure of large numbers of MS31A alleles to be derived from genomic DNA by allele-specific MVR-PCR. More than 100 alleles have now been mapped and all are different. Several alleles show related internal structures and some of these provide evidence of polarity in allelic variation reminiscent of that seen at two other hypervariable minisatellites, D1S8 (MS32) and D16S309 (MS205). We also describe the diploid digital coding of MS31A, including the simultaneous coding of MS31A and a second locus, MS32, by duplex MVR-PCR, which greatly enhances the potential forensic applications of this technique.

Allelic structures at hypervariable minisatellite B6.7 in Japanese show population specificity

“…Remarkably, these groups appear to be completely specific to Japanese or to north Europeans, presumably as the result of rapid mutation after the recent divergence of these two populations. Consistent with this, analysis of more stable minisatellites such as MS31, MS32, and MS205 has shown less extreme population specificity, with groups of related alleles often only partially specific to a given population and frequently shared between populations (Jeffreys et al 1991;Tamaki et al 1992b;Neil and Jeffreys 1993;Huang et al 1996;Armour et al 1996). Allele groups identified at highly unstable loci such as B6.7 may therefore provide useful markers for exploring very recent events such as population bottlenecks, expansions, and migration.…”

“…Japanese alleles of hypervariable minisatellites such as MS32, MS31A, and MS205 have been characterised previously by MVR-PCR (Jeffreys et al 1991;Tamaki et al 1992b;Neil and Jeffreys 1993;Huang et al 1996;Armour et al 1996). Japanese alleles showed high levels of variety as well as north European alleles.…”

“…MVR-PCR followed by agarose gel electrophoresis and Southern blot hybridisation allows such interspersion patterns to be displayed as ladders of PCR products. This approach has revealed enormous levels of allelic variation at several hypervariable minisatellites (Jeffreys et al 1991;Neil and Jeffreys 1993;Armour et al 1993;Buard and Vergnaud 1994;Andreassen and Olaisen 1998;Tamaki et al 1999).…”

Minisatellite MS32 Alleles Show Population Specificity Among Thai, Chinese, and Japanese

“…MVR-PCR followed by agarose gel electrophoresis and Southern blot hybridization allows such interspersion patterns to be displayed as ladders of PCR products. This approach has revealed enormous levels of allelic variation at several hypervariable minisatellites (Jeffreys et al 1991;Neil and Jeffreys 1993;Armour et al 1993;Buard and Vergnaud 1994;Andreassen and Olaisen 1998;Tamaki et al 1999). At the D1S8 locus (minisatellite MS32), almost all alleles in several ethnic populations surveyed were different.…”

Human tandem repeat sequences in forensic DNA typing

“…Some work has been done on labeling the variant primers with different colored fluorescent tags and amplifying both sets of MVR products in a single reaction, to facilitate comparison of the complementary MVR profiles [19,20]. MVR-PCR has revealed enormous levels of allelic variation at several human hypervariable minisatellites; MS32 (D1S8) [17, [21][22][23], MS31A (D7S21) [24,25], MS205 (D16S309) [26,27], CEBl (D2S90) [28], g3 (D7S22) [29], YNH24 (D2S44) [30], B6.7 [31,32] and insulin minisatellite [33].…”