Southeast Asian diversity: first insights into the complex mtDNA structure of Laos

Abstract

BackgroundVast migrations and subsequent assimilation processes have shaped the genetic composition of Southeast Asia, an area of close contact between several major ethnic groups. To better characterize the genetic variation of this region, we analyzed the entire mtDNA control region of 214 unrelated donors from Laos according to highest forensic quality standards. To detail the phylogeny, we inspected selected SNPs from the mtDNA coding region. For a posteriori data quality control, quasi-median network constructions and autosomal STR typing were performed. In order to describe the mtDNA setup of Laos more thoroughly, the data were subjected to population genetic comparisons with 16 East Asian groups.ResultsThe Laos sample exhibited ample mtDNA diversity, reflecting the huge number of ethnic groups listed. We found several new, so far undescribed mtDNA lineages in this dataset and surrounding populations. The Laos population was characteristic in terms of haplotype composition and genetic structure, however, genetic comparisons with other Southeast Asian populations revealed limited, but significant genetic differentiation. Notable differences in the maternal relationship to the major indigenous Southeast Asian ethnolinguistic groups were detected.ConclusionsIn this study, we portray the great mtDNA variety of Laos for the first time. Our findings will contribute to clarify the migration history of the region. They encourage setting up regional and subpopulation databases, especially for forensic applications. The Laotian sequences will be incorporated into the collaborative EMPOP mtDNA database http://www.empop.org upon publication and will be available as the first mtDNA reference data for this country.

Mitochondrial DNA Control Region Variation from Bangladesh: Sequence Analysis for the Establishment of a Forensic Database

“…It also suggest that China, near Tibet, as a possible origin, from there they entered Myanmar around the 6th-7th century AD, where they still live in large number. Some group might be then migrated to Bangladesh and Thailand [25].…”

Mitochondrial DNA-HVR1 Variation Reveals Genetic Heterogeneity in Thai-Isan Peoples from the Lower Region of Northeastern Thailand

“…The number of intrapopulation MPD were 7.5657 (Isan-Ub), 7.8086 (Isan-Bu), and 7.2660 (Isan-Ch), reflected higher genetic heterogeneity within Isan-Bu than Isan-Ub and Isan-Ch. The interpopulation MPD, ranged from 7.6749 to 7.9394, were relatively high compared to previous report (Bodner et al, 2011) reflecting genetic differentiation among them. Genetic structure among the populations was tested for significant variation by AMOVA (Excoffier et al, 1992).…”

“…Because of an extensively ethnic diversity as described in Bodner et al (2011), the contribution from parental Lao in LPRD to the admixed Thai-Isan populations might not be purely from the Tai-Kadai speaking Lao, but the MonKhmer and Hmong-Mien Laos could also be the sources.…”

“…However, it should be cautioned that the Lao samples in LPRD from Bodner et al (2011) which were used as parental populations were multi-ethnic in origin and from across the country, and there is no data of ethnic or linguistic affiliation of each sample. Because of an extensively ethnic diversity as described in Bodner et al (2011), the contribution from parental Lao in LPRD to the admixed Thai-Isan populations might not be purely from the Tai-Kadai speaking Lao, but the MonKhmer and Hmong-Mien Laos could also be the sources.…”

Research Article Mitochondrial DNA control region analysis of three ethnic populations in lower Northern part of Thailand.

“…The HVR-1 π i in Hmong, Lao Song, and Thai-Siam populations was 0.02365, 0.02112, and 0.02110, respectively. Several studies on several populations in Thailand reported the range of the HVR-1 H d , which varied from 0.931 to 1.000, and that of π i varied from 0.0169 to 0.0235 (Fucharoen et al, 2001;Lertrit et al, 2008;Bodner et al, 2011;Boonsoda et al, 2013;Kutanan et al, 2014). These values indicated that the genetic diversity of the three ethnic populations in this study were relatively high.…”