Laos is a state of Indochina Peninsula (also mainland SE Asia) hosting a huge ethnic diversity. As many as 49 ethnic groups are acknowledged nowadays, often divided into lowland (Lao and others, mostly of Kradai languages), midland (Mon-Khmer and others of mostly Austroasiatic languages) and highland peoples (Hmong and others of Hmong-Mien and Tibeto-Burman languages).
As far as I know the genetics of this part of the World had not been explored in until now:
Martin Bodner et al., Southeast Asian diversity: first insights into the complex mtDNA structure of Laos. BMC Evolutionary Biology. Open access.
|Fig. 3 - PCA|
I'll excerpt some of the paper's most interesting insights here:
Major haplogroups and macrohaplogroup structure:
The most prevalent haplogroups were B5a (12%), F1a1a (7.5%), C7 and M7b1 (6% each).
Macrohaplogroup N (including haplogroups A, B, F, N and R) comprised 57% of the samples in 37 haplogroups. 26% of the samples were assigned to haplogroup B, almost equally to B4 and B5. 26 out of the 27 haplogroup B5 samples were found to be haplogroup B5a. 22% of the samples belonged to haplogroup F, of which 79% belonged to F1a and its subhaplogroups.
Macrohaplogroup M (including haplogroups C, D, G and M) comprised 43% in 27 haplogroups. 32% of the samples belonged to haplogroup M, distributed among ten subhaplogroups. 25% of the M samples, however, remained M*. No maternal west Eurasian or African admixture was detected.
The recently described haplogroup M71 was diverse in the Laos sample.
Characteristics of Laotians and some control populations:
The Laos sample showed mtDNA diversity characteristic of Southeast Asian populations. The composition of haplogroups was in agreement with other populations from this region [3- 7,12,17,23-25,35], with haplogroups B4a, B5a, M7b1, F1a and R9 being the most frequent southern aboriginal lineages.
Little Northern contribution was detected. The presence of haplogroups described as Northern (East) Asian [4,6,7,25,36], i.e. A, Z, Y, C, M8a, M9, G2, D and N9, was low in the Laos dataset.
Obviously, the Han population samples did not cluster in the correspondence analysis. Although assigned to the same nationality, they are distant from each other genetically.
It was also meaningful to separate the Hmong and Mien population samples , that are usually combined based on linguistics, as they differ genetically (see Figure 4).
Fast post-OoA migration confirmed:
... the novel basal M haplogroups found in high diversity in the Laos sample and surrounding populations support the fast migration and in situ differentiation model (see Figure 3).
In spite of language Laotians are closest to Austroasiatics than Daics:
An interesting picture was revealed (see Additional Files 6, 7 and 8, Figure 4): the ethnic population with the highest similarity to the Laos sample in terms of shared haplotypes, MPD, pairwise FST values and localization in the MDS plot were the Austro-Asiatic . This was unexpected...
... unexpected probably because the assumptions of the authors about the recent demographic history of the region (full of mass migrations towards the mountaintops - what?!) just do not seem to make much sense.