Recently a Bohra Patel emailed me to express some exasperation that people are quoting me saying that the ancestry of South Asian Muslims is almost all from Hindus (or non-Muslims). Basically, I say things like this “99% of the ancestry of South Asian Muslims is indigenous.” This means some people are going to be 75% indigenous, but the majority probably have no West Asian segments of DNA. This does not mean they don’t have a genealogical line of descent. I myself am ~100% South Asian if you look at my genes…but my maternal grandmother’s father was from a lineage that had migrated to Bengal in the 19th century from Delhi. Before they were in Delhi they had left Persia in the 17th century with the forced conversion of the whole religious class to Shia Islam. This is validated through a Koran with all direct male line descendants listened. I am not one of those descendants (my maternal grandmother is not “in the book”), but I’m pretty sure my distant cousins who are paternal descendants no longer have any detectable Iranian ancestry either. Why?

The reason is that eight generations back there is only a 50% chance that you will any segment of identifiable DNA from an ancestor. Another way to say this is that 200 years ago you had many ancestors, but there’s only a 1 out of 2 probability that you will have identifiable DNA passed down through the generations from that person. Since my Iranian lineage (a man who left Iran, settled in South Asia, and married into the South Asian Muslim community) dates back 350 years, it’s totally unsurprising that there’s no evidence that isn’t documentary at this point.

In any case, I’m looking more closely at the assertion I made above. I ran a supervised analysis on some samples. You can see the results below. I’ll probably do f-stats too…but that takes a while to run. I may ‘update’ my estimate from 1% to closer to 5%, though I’m not convinced. The Bohra Patel is in the sample, it’s clear they are enriched for “Yemenite Jewish” ancestry. But, even with 200,000 markers, there are Hindu individuals that are 1-2% (Tamil Brahmin) because of the way the model is set up.

Really what’s needed are huge Y chromosome panels. Since that’s an unbroken lineage, and the gene flow is mostly through men from everything we know.

But the real problem is Iranian ancestry because there is something of a “cline” in the northwest of the subcontinent. How exactly are we supposed to detect Iranian ancestry in Punjabis that is recent? Ultimately it’s going to have to be IBD segments in large panels.

That being said, there is an indirect way to detect Muslim West Asian ancestry: look for Turkic and African segments. These come from Muslims, and so can serve as a tracer that is much more distinct from the Indian genetic landscape.

Finally, the flip side of these comments about the minimal impact of West Asians on the genes of South Asian Muslims is that it should make us more skeptical of the arguments of some Hindu nationalists and Muslim fundamentalists about how brutal the Turks were. I’m sure they were brutal…but they didn’t leave much of a genetic impact on Muslims, let alone Hindus. Most people were likely pretty insulated from the predations, probably because cities were demographic sinks anyhow.

Continue reading West Asian ancestry in South Asian Muslims

Decided to start reading India in the Persianate Age: 1000–1765. It’s a fast and easy read (and, it’s an affordable book for a nonspecialist like me who only spends $100 or more on genetics texts). I jumped ahead in a few passages, which seem to be adaptations from papers I’ve read from the author before.

In relation to discussions on this weblog and comments I’ve made:

1) The author describes islands and pockets of wholly Muslim peasants in eastern Bengal observed by the Mughals in the 16th century. These Mughals indicate that these people are not truly Hindu or Muslim, at least initially. This is line the common thesis that Islamicization is a function of the weak to nonexistent integration of these frontier peasants into Indian culture. Mughal observers also note the physical appearance of these people: small, dark-skinned, and beardless. This seems entirely accurate (I cannot grow a beard!).

The author observes that tax receipts over several decades in Bengal exhibited a pattern that is suggestive of a massive population increase in the east and stability in the west. In fact, there were two-fold increases in the east at the same time that districts in the west declined by 10%.

The thesis by the author, which seems broadly creditable, though not proven, is that the transition to high-intensity rice agriculture in the plains of the eastern delta, and in particular east of the Padma, arrived after the Mughal expansion into the reason. As such, the transition to a “higher religion” occurred under Islam, and therefore these people became Muslim (at least nominally). The analogy that is obvious here would be the Christianization of the Montagnards and other Southeast Asian “hill people” during the colonial period, as they had been detached from Theravada Buddhist civilization.

2) The author deploys a similar model, with modifications, for western Punjab. The model here is that Jat who moved up from Sindh abandoned obligate pastoralism and engaged in agriculture, and fixated upon the tombs and shrines of Islamic eminences. Due to the emphasis on paternal lineage, the author observes that the Islamicization of names occurred quantitatively over 300 years, from the 15th to the 18th century (initiation to completion).

The main qualm I have with this model is this: the Jats/people of Punjab do not look to be from Sindh if modern Sindhis are representative of ancient Sindhis. In the language familiar to readers of this weblog Sindhis are enriched for “Iranian-related ancestry” vis-a-vis Punjabis, who are enriched for “steppe.” The Jats in particular are highly enriched for “steppe” ancestry. Going by genetics alone this model is difficult to accept, though as noted in this space it does seem that caste-like stratification has ancient roots in this region, and so that may serve as some explanation.

Note: The model in Bengal implies that Islamicization and Hinduicization occurred in East Bengal simultaneously. That is, most of the sponsors of agricultural reform and intensification happened to be Muslim, but some were Hindu, and in the case of Hindu sponsored developments the regions became Hindu. Further investigation though would be warranted for Bengali Brahmins in the eastern regions, who would then presumably be migrants from the western zone, because it is hard to credit animistic tribes needing the services of literate priestly elites.

Since many readers of this weblog have rather naive views of Islam and its interaction with the Indian subcontinent, I thought they might appreciate my post on my other weblog, The Myth Of Arabian Paganism, And The Jewish-Christian Origins Of The Umayyads.

It wasn’t emphasized in the piece, but I will make it clear here: the development of Sunni Islam as we understand it was strongly conditioned on the cultural influences from the matrix of Iranian-Indian religious and social thought which matured in Turan. In fact, one of the early Abbasids, the son of an Iranian mother, even considered moving the capital of the Caliphate to Central Asia, in particular, the city of Merv.

The aspects of Islamic thought most clearly a product of this period and place? I believe that this is the hadith culture embedded within the institutions of the madrassa. Many argue the madrassa is a modification of the Central Asia vihara, and the analysis of proper practice due to religious law was a major function of the religious within these viharas.