August 03, 2005

Forensic informativeness of mtDNA haplogroup H

mtDNA haplogroup H occurs very frequently in Caucasoids. This means that even if additional HVRI/HVRII information is known, there is still a high probability that two H samples with the same mutations in the hypervariable regions may not in fact be closely related. Testing for the sub-haplogroups of H is a way in which additional information about haplogroup H samples may be obtained. The authors find that this is quite useful and that the distribution of H sub-haplogroups is significantly correlated with geography. From the article:
Most of the European populations sampled display an overall haplogroup H frequency of ~40–50%, with frequencies decreasing towards the south-east, reaching ~20% in the Near East and Caucasus, and ~65% of haplogroup H lineages in Iberia, ~46% in the north-west, ~27% in central and eastern Europeans, and ~5–15% in the Near East/Caucasus, and are absent from the Gulf. The frequency of H5a appears to be highest on the central European plain; it occurs at low levels across Europe but is absent from the Caucasus and the Near East. H2 and H6 are both common in Eastern Europe and the Caucasus, and are not found in the Near Eastern sample. The less common sub-clades H4, H7 and H13 occur in both Europe and the Near East; H13 also present in the Caucasus. The paraphyletic cluster H* predominates in the Near East, its range at least partly the mirror-image of that for H1 and H3, but it is most common in East–Central Europe and the Balkans, and is frequent in Atlantic Europe as well.

Forensic Science International (Article in Press)

Evaluating the forensic informativeness of mtDNA haplogroup H sub-typing on a Eurasian scale

Luísa Pereira et al.


The impact of phylogeographic information on mtDNA forensics has been limited to the quality control of published sequences and databases. In this work we use the information already available on Eurasian mtDNA phylogeography to guide the choice of coding-region SNPs for previous termhaplogroupnext term H. This sub-typing is particularly important in forensics since, even when sequencing both HVRI and HVRII, the discriminating power is low in some Eurasian populations. We show that a small set (eight) of coding-region SNPs resolves a substantial proportion of the identical haplotypes, as defined by control-region variation alone. Moreover, this SNP set, while substantially increasing the discriminating efficiency in most Eurasian populations by roughly equal amounts, discloses population-specific profiles.


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