No true Sardinian

I am led to believe that other genetic samples from Sardinia don’t necessarily show the same degree of weirdness that you see in the HGDP samples: they look more admixed, more cosmopolitan.  The guess is that Cavalli-Sforza knew what he was doing, and chose samples from the most isolated, mountainous, gnarly villages.

In a way, this should encourage people searching for genetic traces of the far past.  What we see in those HGDP samples is not just a product of the unique history and ecology of Sardinia (although that surely helped) – it also depended on very local effects. This suggests that you might find interesting genetics in a number of out-of-the-way, hard-to-get-to corners of the world. Places that the tax-collectors couldn’t even reach.  Maybe even in Europe, not just in Kafiristan or Shangri-La.

 

 

 

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37 Responses to No true Sardinian

  1. I keep reading that the Kalash are significantly genetically isolated but isn’t that because of sampling ? no one bothers to sample the Kalash who have converted (and conversion is a continuing process) and in Chitral there is a population of Muslim Kalash speakers who are simply referred to as Chitralis. Then you’ve got the general Khowar-speaking population of Chitral and has anyone sampled them ? in fact it would seem speakers of Dardic languages aren’t sampled at all. I wager the Kalash wouldn’t seem nearly as isolated if the fellow Dards were better known genetically. How about Kashmiris ? They are also Dards, if you air-dropped swabs over Bradford and Oldham you couldn’t fail to get saliva samples….

  2. cavalli-sforza’s interest in linguistic and sectarian isolates casts a big legacy on pop gen which overestimates the genetic isolation of some of these groups ?

    • gcochran9 says:

      They’re just as isolated as they look. If people from village X in Sardinia look amazingly like Otzi or an LBK farmer, and almost completely lack a genetic component common in other modern Europeans, that’s the way it is. If people in some coastal Sardinian city look more admixed, then they are.

      • but your point was that we know Sardinian highlanders are different because we also have information about the adjacent population, Sardinian lowlanders. is that true of all isolates we know about and their neighbours ?

  3. dearieme says:

    “Places that the tax-collectors couldn’t even reach. Maybe even in Europe”: hush! Don’t tell everyone.

  4. Paul Conroy says:

    Aran Islands – off the West coast of Ireland – would be another place to look.

    Typical Irishman – per Harvard Survey from decades ago:
    The composite Irishman, representing the mean of ten thousand of his countrymen, is 35 years old, 172 cm. tall, and weighs 157 pounds. He is well built, muscular, and large boned, with shoulders 39 cm. broad, and a trunk length which is 53.3 per cent of his total height. His arms are long, and his span is 105.3 per cent of his stature. So far, his bodily dimensions and proportions might be matched among western Norwegians, Icelanders, many Swedes, Livs, and Finns of Finland. His head is large, for Ireland has consistently the largest head size of any equal land area in Europe. The three principal vault dimensions of his head, 196 mm. by 154 mm. by 125 mm., give him the mesocephalic cephalic index of nearly 79, and the moderately hypsicephalic length-height index of 64. His cranial vault, like his body, could again be matched among the larger-headed peoples of Scandinavia and the Baltic lands.

    Aran Islands:
    The regional differences are not great, with a single exception, that of the Aran Isles. The hypermarginal, culturally conservative Gaelic speakers of these islands seem to have formed, in isolation and by interbreeding, a distinct local racial entity. They are the tallest Irish group, with a mean stature of 174.5 cm.; they are longer legged, leaner, and lighter in weight than most of the others; their head length mean reaches the excessive dimension of 198.3 mm., while their head height, 120.3 mm., is extremely low. Thus they have the relatively low cephalic index of 77.8, and the orthocephalic length-height index of 60.7. Their total face height reaches the extreme mean of 130 mm., their nose height of 57. It is impossible, at present at least, to discover a continental prototype for the Aran Island racial dimensions. For the moment we must consider it a local development of race-forming proportions.

    • Andrew says:

      I recall this article from the Atlantic, Jim Fallows tested 5% Neanderthal with speculation that his mother’s line has the most Neander admixture and this was due to her origins being isolated in Scotland.

      http://www.theatlantic.com/technology/archive/2012/10/at-5-neanderthal-you-are-an-outlier/263475/

      • Paul Conroy says:

        @Andrew,
        Fascinating – somehow I missed that story when it came out.

        BTW, my father who AFAIK is 100% Native Irish – and to date the only person who can claim that of the thousands of Irish who have tested with 23andme. Compared to other Irish he shows the highest proportion of Basque ancestry PLUS the highest proportion of Scandinavian ancestry (Danish to be exact).
        On 23andme, he is placed the furthest NW of anyone in Northern Europe – likely because of this. On their Ancestry Composition he used to show a small segment of Oceanian?! On various other calculators, he frequently shows a small segment of the population that is the most outlying of those being compared, so in some cases it is Oceanian, San, Pygmy, Denisovan or whatever.
        Dienekes produced a calculator some time back, which had an outgroup of Chimpanzee, and my father scored a segment of Chimpanzee based on that?!

  5. Flinders Petrie says:

    Perhaps Cavalli-Sforza spoke with someone like Gonario, the Orgolesi shepherd, who knew the difference between traditional Sards versus suspected descendants of Roman concubines and cuckolds.

    Those mountain shepherd bars seem like fun places to visit.

  6. Matt says:

    For an example, there are a few other Italian population isolates in this paper, from the Northeast Italian region of Friuli-Venezia Giulia.

    http://www.nature.com/ejhg/journal/v21/n6/full/ejhg2012229a.html

    In the data supplement to the paper, on a world PCA, they seem to sit almost as much outside the general European cline as Sardinians (having a slightly further distance on the European-Asian dimension than they would be expected to for based on the European cline) but in slightly different position, parallel to Slovenes and Northern Italians where .Sardinians are parallel to Southeast Italians.

    http://www.nature.com/ejhg/journal/v21/n6/extref/ejhg2012229x3.pdf

  7. dearieme says:

    Perhaps someone should get permission to do some DNA testing of human remains on St Kilda.
    Or, if the rats didn’t get ’em all, North Rona.

  8. Bones and Behaviours says:

    I’d like to see Cagot aDNA sampled just to settle their origins.

  9. Paul Conroy says:

    It would also be interesting to do a full autosomal analysis of some of the inhabitants of the island of Hvar, off the coast of Croatia, as the population has 8.3% mtDNA F, which is usually found in SouthEast Asia?!
    http://www.ncbi.nlm.nih.gov/pubmed/11571562

  10. dave chamberlin says:

    I would love to know what percentage Denisovan the last pure Tasmanians were. Cochran mentioned in a chat he had with Razib on Blogging Heads a few years back that 3000 years ago 10% of the population of Croatia had pronounced brow ridges. The problem is some people want our past to stay hidden, which I find silly. Nobody is using this information to insult anybody, it is just a fascinating window into our almost entirely lost distant past.

    • The fourth doorman of the apocalypse says:

      There appears to be more diversity in head shapes among Chinese and Japanese than I have seen among Caucasians …

      I have seen one Chinese individual and one Japanese individual with strongly sloping foreheads (and wide heads) and I have not seen such among Caucasians and had never seen such before among the Chinese I have associated with, which includes both Southern Chinese and Northern Chinese. Both individuals were of above average intelligence (well, if working in high tech and being able to write code using the sockets interface etc is evidence of above average intelligence.) I doubt that their parents strapped their heads in shaping devices when they were babies.

      It would be interesting to know their genetic backgrounds.

      • gcochran9 says:

        Some form of untreated craniosynostosis is a possibility.

        Which reminds me… There were two brothers with pointy heads in my school: naturally people picked on them, because people are jerks. And if memory serves, they were fairly obnoxious, too. Anyhow, we got a new teacher who was doing some sort of counseling (one of her sons became a good friend of mine) – a teacher who had not grown up in the town and had recently arrived. She thought that perhaps something should be done for those pointy-headed brothers, and arranged a conference with their parents. She was all ready to give her spiel – and then their Dad took off his hat.

      • The fourth doorman of the apocalypse says:

        Uh oh. Seems I did not know about this:

        http://www.asianplasticsurgeryguide.com/foreheadaugmentation/a_forehead.html

        Looks like it might just be part of the diversity of Asian Features.

      • Sandgroper says:

        A selection of normal Chinese heads:

      • Matt says:

        AFAIK East Asian folks have pretty globular brains (high, wide and short) and an average sized brain base, which would naturally lead to not so much of the bulging of the frontal bone typical of Modern Humans, which is a consequence of AMH’s anterior-poster (front to back) long and large brains built on a small cranial base* (so the frontal part of the brain has to bulge out). Instead that more sloping shape. Unless the East Asian person does have a relatively small cranial base.

        *AMH’s brains are somewhat more globular than ancient Homo though (although funnily enough this is not a trait which increases from chimps to ancestral Homo).

    • Bones and Behaviours says:

      If Cochran or Razib read this, can someone provide evidence that “3000 years ago 10% of the population of Croatia had pronounced brow ridges” please. It sounds kind of interesting.

  11. dearieme says:

    “Nobody is using this information to insult anybody”: they will, Dave, they will. Not that that’s a good reason not to press on.

    • dave chamberlin says:

      You are absolutely right, BUT. Do we need to continue to censor science when it makes someone somewhere sensitive. My motto is fuck’em if they can’t take a joke and jok’em if they can’t take a fuck but I have to admit it hasn’t got me very far.

  12. Steve Sailer says:

    It sounds like a fun job: finding the most isolated, xenophobic villages to collect genetic samples from.

    Carleton Coon took a lot of pride in how well he got along with mountain villagers in Albania and the Maghreb. Not surprisingly, Coon’s autobiography recounts more fistfights than the average academic’s. The OSS assigned him to be the Lawrence of Morocco in case Franco let the German Army come through Spain to attack Bradley and Patton from behind in North Africa — Coon was supposed to disappear into the mountains and rally his Berber friends to raid the German Army.

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  14. Greying Wanderer says:

    There’d be odd bits of old dna in the North Wales mountains imo

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