Comments on: ADMIXTURE vs. MDS, visualization is just visualization

By: The genomic heritage of French Canadians | Gene Expression | Discover Magazine

Mon, 24 Jan 2011 09:02:44 +0000

[...] One of the great things about the mass personal genomic revolution is that it allows people to have direct access to their own information. This is important for the more than 90% of the human population which has sketchy genealogical records. But even with genealogical records there are often omissions and biases in transmission of information. This is one reason that HAP, Dodecad, and Eurogenes BGA are so interesting: they combine what people already know with scientific genealogy. This intersection can often be very inferentially fruitful. [...]

By: ohwilleke

ohwilleke — Thu, 20 Jan 2011 21:50:09 +0000

I am aware that a few people have done three dimensional MDS plots and have seen one or two. I’d be curious to hear what people think about their usefulness.

By: pconroy

pconroy — Tue, 18 Jan 2011 22:34:12 +0000

No, but whatever it is, it’s only a minor portion of other Indian samples – so IMO it must be due to:
1. Isolation by distance – like Sardinia – which is not likely
2. Isolation by religion/caste – like Assyrian
3. Ancient substrate
4. Exogenous to India – like Austronesian admixture

I guess there is some likelihood of #1 or #2 – if the sample was all sourced from an isolated mountain village or religious minority, but usually in understudied areas, samples are from cities, and rarely rural areas.

By: Razib Khan

Razib Khan — Tue, 18 Jan 2011 21:58:57 +0000

u wouldn’t happen to know what the detailed origin of the north kannadi sample is, would you?

By: pconroy

pconroy — Tue, 18 Jan 2011 21:56:50 +0000

Razib,

Very interesting, as this would fall in line with my speculation that the mystery component of the North Kannadi could be Austronesian – and depending on how one defines Austronesians and their expansion – slow boat/fast boat etc – they could be seen as South East Asian + Oceania or at least island South East Asian