Singapore Indians

In the South Asian PCA plot, we saw that Singapore Indian samples from the SGVP dataset had a lot of diversity. Let's zoom into that plot so it's not dominated by the distinctiveness of the Kalash.

Eigenvector 1 explains 1.45 times the variation compared to eigenvector 2.

We see that Singapore Indians are spread in the whole region from Sindhis to North Kanaddi.

Now let's look at the individual admixture results (at K=12 ancestral populations) for the Singapore Indians. I have added some South Asian reference population averages so you can place them in context.

You can click on the legend to the right of the bar chart to sort by different ancestral components.

From these results, a majority of the Singapore Indian samples look South Indian but there are definitely a few from the northwest of the subcontinent (Punjabis or Sindhis?) There are also a few who could be from the Hindi belt.

There are 2-3 samples who have a significant amount of Southeast Asian. Could they be originally from Bengal? Or could they have partial Singapore Malay ancestry?


  1. Arranging the chart by Component 1 is good for a quick rundown. Aside from SE Asian or European admixed members in a few cases, we can all see the West Asian component in the Jewish groups. And, of course, we can see the full cline in South Asian among the Singapore Indians.

    For most of the range, the cline looks pretty steady. But what a range it is!

  2. zack, i think a few bengalis within the list seems plausible from what little i know of singapore indians. this is a majority tamil group, but not totally so. there are a smattering of others, particular in the more recent waves of professionals and among the older mercantile groups.

  3. looked it up. ethnic tamils are ~60% of indians in singapore.

  4. The SGVP450 having 41% euro seems weird, and lower south asian than the pathans. From the admixture profile , it looks most likely that the other non-tamils are probably sindhi( there are quite a fair bit of them in singapore).

    • SGVP450 clearly has recent European ancestry (probably West/Northern) as their Pak-Cauc component is not proportionally raised with the European in the manner expected from recent Pathan or Jatt ancestry.

      The Singapore Indians are quite diverse, but as pointed out before, the modal of these samples is one with >~70% South Asian. This is consistent with them being from further south (i.e. Tamil Nadu).

  5. Very interesting plot, reminiscient of the Northern European Plain one published by Dienekes:
    I think not using Kalash may be more informative, also maybe using the new ADMIXTURE pole-setting tool.

    I realise you lack samples from many important populations, I can't stop wondering if the major clusters, gaps apparent don't represent admixture events between different food producing revolutions.

    From the West you may have an earlier agricultural expansion from (North)Eastern Iran/South Mesopotamia? And then Indo-Aryan pastoralists from the Kurgan Culture. +East/SouthEast-Asians with Rice.

    I personally doubt the Arabs/Turks are responsible for this... In Europe it's increasingly apparent that Neolithic populations from the Near East are the dominant element, one is almost forced to think of Complete Replacement :). Later invasions were of likely minor consequence.

    In South Asia, particularly in South India, I think a third native element is a possibility, considering some native crops of unknown antiquity+Genetic diversity.

    By the way, I have 2% "South Asian" if you're ever interested :). Would love to know if it comes from Goa.

    • I am going to exclude Kalash from later PCA computation but in this case, Kalash was in the data, I have just zoomed in to look at all the other populations.

      2% South Asian is very likely to be noise in my opinion.