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Milk drinkers came from Ural Mts. in Russia

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  • Milk drinkers came from Ural Mts. in Russia

    This is a reprint of a Science Magazine article (whose full text from that magazine's web site costs money):

    http://www.freerepublic.com/focus/f-news/1284595/posts
    ---
    Now, Peltonen's team has tried to trace the origins of lactose tolerance by looking at 1611 DNA samples from 37 populations on four continents.

    The populations having the greatest DNA sequence diversity around the lactase gene mutations--suggesting that lactose tolerance first appeared in them--include the Udmurts, Mokshas, Ezras, and other groups that originally lived between the Ural mountains and the Volga River. The trait most likely developed 4800 to 6600 years ago, Peltonen says. Her team linked the lactase gene changes to an ancestral variant that these groups apparently got from intermixing with tribes migrating from the Asian steppes.

    After the Ural peoples gained this earlier form of the lactase gene, the lactose tolerance mutation "probably emerged by chance," says Peltonen, and then remained because it was beneficial for milk consumption. The Ural groups then likely later spread the variant to Europe--especially northern Europe, which has the highest lactose tolerance today--and the Middle East.
    ---

  • #2
    Larry,

    Very interesting article. I did not know that Cavalli-Sforza had integrated the competing Kurgan and Anatolia theories about who spread IE languages throughout Europe:

    ""I find [the new study] very interesting," says population geneticist Luigi Luca Cavalli-Sforza of Stanford University. He notes that a competing idea for explaining the origin of the Proto-Indo-Europeans is that they were crop-growing farmers from the Anatolia region in modern Turkey (Science, 27 February, p. 1323). But the milk study reinforces Cavalli-Sforza's view that both theories are correct: Indo-Europeans migrated to Europe in two waves, first from Turkey and later from the Urals."

    I wonder why Dr. Peltonen's study (2004) and its conclusions were not mentioned in some of the more recent publications dealing with lactose tolerance? Drs. Thomas and Burger seem to believe the mutation occurred in northern europe. The origin of the mutation has some very important ramnifications for the population history of europe.

    John

    Comment


    • #3
      Larry,

      I have found another abstract dealing with this issue:

      "Lactose persistence in prehistoric individuals
      Fulge M., Renneberg R., Hummel S., Herrmann B.
      Historical Anthropology and Human Ecology, Johann Friedrich Blumenbach-Institute of Zoology und Anthropology, University of Göttingen

      Introduction: The dietary habits of ancient populations are often issues of
      stake. With the domestication of animals like cattle, sheep and goat these
      habits changed. The question since when milk and its products were used as
      daily life aliment is of special interest, because the normal condition in
      mammals is that after the lactation period they are not able to digest lactose.
      In 95% of the European individuals the state of lactose tolerance maintains,
      whereas in Africa and Asia 95% are lactose intolerant. The point of time and the place of development of the lactase persistence are in request. Two different theories of it exist. One is that the lactose tolerance developed in Anatolia in the Neolithic period and would have spread in Europe 8000 years ago. The other theory declares a nomadic tribe (Kurgan culture) as population of origin. Following this theory the lactose tolerance would have
      spread 4500-3500 years ago. One method to detect the status of the digesting ability of lactose is to determine the pointmutation C/T (-13910) which is linked to the lactase gene. If a T is realized (homo- or heterozygote) you are able to digest lactose. In this study we investigated this mutation in 38 individuals of the Bronze Age Lichtenstein Cave and in nine Celtic individuals from Manching to get a clue when the lactose tolerance was spread in Europe.

      Materials and Methods: The DNA was extracted of femora and mandibles with
      a silica-based method on the EZ1-extraction robot (Qiagen). For detecting the pointmutation a dye labelled primer was designed. The upper primer contained a mismatch which permits the digestion with HinfI if thymidin is realized at the position 13910. For proving the authenticity of the results the lactose Primer was coamplified with six autosomal STRs.

      Results and Perspective: The lactose genotype could be amplified and
      authenticated in 27 Individuals of the Lichtenstein Cave. About 60% were
      lactose tolerant and around 40% were intolerant. Similar results were detected in the nine Celtic individuals: around 50% was lactose intolerant. These high rates of intolerant individuals suggest that even if stock farming was done consume of milk was not a daily habit. These results give a hint that lactose tolerance was not only spread 8000 years ago. For proving this thesis earlier and later populations should be analysed."

      In yet another article, Dr. Sarah Tishkoff of the University of Maryland, in 2006 discussed the european lactose tolerance mutation and stated:

      "Such a mutation is known to have arisen among an early cattle-raising people, the Funnel Beaker culture, which flourished some 5,000 to 6,000 years ago in north-central Europe. People with a persistently active lactase gene have no problem digesting milk and are said to be lactose tolerant."

      http://www.nytimes.com/2006/12/10/sc...rssnyt&emc=rss

      John

      Comment


      • #4
        Interesting. Perhaps Neolithic archaeologists are 'catching' the lactase persistence allele just as it was ramping up in Europe. The Lichtenstein Cave that your source mentions is from the Bronze Age, about 3000 years old, suggesting that as late as 1000 B.C., about half the population of central Europe was still lactose-intolerant.

        This paper did not find the allele in earlier, Neolithic remains:

        http://www.ucl.ac.uk/tcga/tcgapdf/Bu...7_LCT-aDNA.pdf
        ---
        By applying this experimental strategy, we have obtained high-confidence LP-associated genotypes from eight Neolithic and one Mesolithic human remains, using a range of strict criteria for ancient DNA work. We did not observe the allele most commonly associated with LP in Europeans, thus providing evidence for the culture-historical hypothesis, and indicating that LP was rare in early European farmers.
        ...
        However, forward computer simulations have shown that the center of distribution of an allele can be far removed from its location of origin when a population expands along a wave front (55). Geographic structuring of haplotype diversity among 13.910*T-carrying lineages may prove to be a more reliable indicator of the region of origin, and in a preliminary report, Enattah et al. (56) have used this approach to infer an eastern, possibly steppe, origin for the 13.910*T allele.
        ---
        Last edited by lgmayka; 19 March 2007, 10:46 AM.

        Comment


        • #5
          The Manching Oppidum, also mentioned in the abstract you cite, is from the Iron Age, about 300 B.C. to 15 B.C.

          Conference on ancient DNA (see page 26 for abstract on lactase persistence)

          Manching Oppidum, from the Iron Age, 300 B.C.-15 B.C.

          Comment


          • #6
            Originally posted by lgmayka
            Interesting. Perhaps Neolithic archaeologists are 'catching' the lactase persistence allele just as it was ramping up in Europe. The Lichtenstein Cave that your source mentions is from the Bronze Age, about 3000 years old, suggesting that as late as 1000 B.C., about half the population of central Europe was still lactose-intolerant.

            This paper did not find the allele in earlier, Neolithic remains:

            http://www.ucl.ac.uk/tcga/tcgapdf/Bu...7_LCT-aDNA.pdf
            ---
            By applying this experimental strategy, we have obtained high-confidence LP-associated genotypes from eight Neolithic and one Mesolithic human remains, using a range of strict criteria for ancient DNA work. We did not observe the allele most commonly associated with LP in Europeans, thus providing evidence for the culture-historical hypothesis, and indicating that LP was rare in early European farmers.
            ...
            However, forward computer simulations have shown that the center of distribution of an allele can be far removed from its location of origin when a population expands along a wave front (55). Geographic structuring of haplotype diversity among 13.910*T-carrying lineages may prove to be a more reliable indicator of the region of origin, and in a preliminary report, Enattah et al. (56) have used this approach to infer an eastern, possibly steppe, origin for the 13.910*T allele.
            ---

            The full discussion about the origin of the mutation may be of interest to readers of this thread:

            "The present study should contribute to archaeological debate
            concerning the origin of dairying in Europe. Although some
            scholars assume that dairying was not practiced during the
            earliest phases of the Neolithic and that it first spread over
            Europe in the 3rd millennium B.C. (47, 48), others, based on
            osteometric sexing of cattle and goats, suggest an onset of
            dairying practices in southeastern Europe and southern Germany
            between 7000 and 6500 B.P. (49). Others claim that the
            technical skill of dairying came to Europe already as part of the
            fully developed Neolithic package with the first farmers (50, 51).
            The latter view is supported by the earliest archaeometric
            evidence for dairying in Europe 7900–7500 B.P. in Hungary
            (52) and 6100 B.P. in Britain (53, 54). These dates suggest that
            dairying practices came to Europe nearly simultaneously with
            cereal agriculture and domestic animals. However, the absence
            of the 13.910*T allele in our Neolithic samples indicates that the
            early farmers in Europe were not yet adapted to the consumption
            of unprocessed milk. Dairying is unlikely to have spread uniformly
            over Europe, and the use of milk in the Early Neolithic
            may have been rare. Although our data are consistent with
            strong selection for LP beginning with the introduction of cattle
            to Europe 8800 B.P., it is unlikely that fresh milk consumption
            was widespread in Europe before frequencies of the 13.910*T
            allele had risen appreciably during the millennia after the onset
            of farming.
            Important questions remain regarding the geographic location
            of the earliest 13.910*T-allele-carrying populations, the mode
            and direction of spread of the allele, and the precise nature of
            the selective advantage(s) conferred by LP. If dairying was a
            common feature of European Neolithic populations, and the
            selection pressure is actually so strong, then an LP-causing
            mutation occurring anywhere in Europe should rise rapidly in
            frequency. A number of approaches are available for inferring
            the geographic origin and direction of spread of an allele by using
            data from modern populations. The modern distribution of the
            13.910*T allele might be taken to indicate a northwestern
            European origin. However, forward computer simulations have
            shown that the center of distribution of an allele can be far
            removed from its location of origin when a population expands
            along a wave front (55). Geographic structuring of haplotype
            diversity among 13.910*T-carrying lineages may prove to be a
            more reliable indicator of the region of origin, and in a preliminary
            report, Enattah et al. (56) have used this approach to infer
            an eastern, possibly steppe, origin for the 13.910*T allele. But,
            as with inference based on allele distribution alone, common
            demographic processes, such as demic diffusion, may obscure
            signals of geographic origin. Although computer simulations
            that accommodate or explore more realistic demographic scenarios
            (e.g., ref. 57) and other parameters, such as selection
            strengths, offer for the future a better understanding of the
            origin, spread, and coevolution of LP and dairying in Europe, all
            inference-based methods for investigating these factors carry a
            high degree of uncertainty. Thus, we believe that an ancient
            DNA approach, the feasibility of which is demonstrated here, is
            the most direct way of studying the evolution of LP in Europe.
            In this study, we provide high-confidence prehistoric lactase
            genotypes from reliably dated remains. One direction for future
            research that should yield a greater insight into the origin,
            evolution, and spread of LP in human populations would be the
            incorporation of our data into the wider computer simulation
            models proposed above."

            Clearly, a lot more study is needed on this subject and the timing of the arrival of various european haplogroups.

            John

            Comment


            • #7
              Goats' milk is tolerated by lactose intolerant adults.

              Adult sustenance milk-drinking. No accident.

              The Chromosome 14 Lactophile Persistence ( LP) mutation appears to have been a directed, quite facile two-way breeding process between humans and cattle as paper A. below indicates. Wherever a tribe-herd community existed, the LP mutation seems a likely outcome. The symbiosis enhanced mobility and nutrition to a degree that facilitated, and by birthrate promoted, multiple tribal migrations resulting in wide (but not uniform) diffusion of the technology and the mutation, the peri-Baltic area the most concentrated by present time.

              Paper A.
              Nature Genetics 35, 311 - 313 (2003)
              Published online: 23 November 2003; | doi:10.1038/ng1263



              Brief Communication.
              Gene-culture coevolution between cattle milk protein genes and human lactase genes


              Milk from domestic cows has been a valuable food source for over 8,000 years, especially in lactose-tolerant human societies that exploit dairy breeds. We studied geographic
              patterns of variation in genes encoding the six most important milk proteins in 70 native European cattle breeds.
              We found substantial geographic coincidence between high diversity in cattle milk genes, locations of the European Neolithic cattle farming sites (>5,000 years ago) and
              present-day lactose tolerance in Europeans. This suggests a gene-culture coevolution between cattle and humans.

              Some, but not all, human populations have the genetically determined ability to digest milk lactose in adulthood, thereby benefiting from the rich food resources in cow's milk1. These societies (e.g., Northern Europe) are lactose-tolerant and highly dependent on milk products.
              Lactose tolerance is an example of selection-based evolutionary change in humans from milk-drinking cultures2.
              Has there also been a detectable evolutionary change in the gene pool of domestic cattle from these cultures? Our study of nonsynonymous mutations in six milk protein
              genes in 20,000 cattle from 70 breeds across Europe (Fig. 1a) found high allelic richness and genetic distinctiveness
              in the native cattle from North Central Europe (NCE), as illustrated by the synthetic map of cattle milk protein genes .

              Supplementary Fig. 1 Notably, this synthetic map (inner contour) closely matches
              the European distribution of the allele for human lactase persistence that is most frequent in NCE (P < 0.0005; Table
              1). This is in stark contrast to the lower levels of lactose tolerance found in people of Southern Europe and the Near East. There was also strong concordance (P < 0.001) of the
              geographic distribution of cattle milk gene diversity with the early Neolithic istribution of a European cattle pastoralist society.
              Figure 1. Geographic coincidence between milk gene diversity in cattle, lactose tolerance in humans and locations of Neolithic cattle farming sites in NCE. (a) Geographic distribution of the 70 cattle breeds (blue
              dots) sampled across Europe and Turkey. (b) Synthetic map showing the first principal component resulting from the allele frequencies at the cattle genes. The dark orange color shows that the greatest milk gene uniqueness and allelic diversity occurs in cattle from NCE. (c) Geographic distribution of the lactase persistence allele in contemporary Europeans. The darker the orange color, the higher is the frequency of the lactase persistence allele. The dashed black line indicates the limits of the geographic distribution of early Neolithic cattle pastoralist (Funnel Beaker Culture) inferred from archaeological data15.


              How can we explain the strong geographic concordance between cattle milk gene diversity, human lactose tolerance and the
              distribution of the earliest European cattle pastoralists?
              We propose that since Neolithic times, there has been gene-culture coevolution between the domestic cattle and human culture driven by the advantages conferred by milk consumption. This led to the maintenance of larger herds and selection for increased milk yield and altered milk protein composition. This coevolution seemingly influenced the frequencies of the important milk protein genes in cattle and the gene encoding lactase in humans. In fact, a recent study suggested that the relatively old variant for lactose
              tolerance was only recently driven to high frequencies in North Central Europeans after the introduction of dairy culture in this region4.
              This scenario is also supported by evidence for selection at milk protein loci in bovids5. For example, directional selection can explain high intraspecific divergence and low
              intraspecific polymorphism in k-casein sequences across bovids5. Our data also show patterns consistent with selection: 19 NCE breeds deviated significantly from
              neutrality.
              Our genetic data corroborate recent archaeological evidence suggesting that the early European cattle pastoralists in
              NCE were dependent on milk as early Neolithic sites in NCE are rich in cattle remains. Based on the analysis of intratooth change in nitrogen isotope ratios from archaeological cattle teeth, it seems that cattle herds were managed for early weaning of calves, making cow's milk more available for human consumption. Meat production, practiced outside NCE, necessitates later weaning to optimize weight gain.
              Among several phenomena that might have shaped our data, selection seems the most probable explanation. Recent studies have shown that high diversity in human genes can evolve rapidly due to selection. In addition, analysis of bovine myostatin alleles showed signals of balancing selection in a number of independently occurring mutations
              that cause double-muscling in beef breeds9.

              Given that population surveys of mtDNA sequence, microsatellite markers and protein polymorphisms in European cattle breeds show no evidence of elevated diversity in NCE it is likely that selection pressure imposed by early pastoralists and their successors in different regions of NCE has left the legacy of high allelic diversity at these specific milk genes.

              **It is also possible that some of the diversity represents relatively recent mutation (<10,000 years), although, under a neutral model, mutation rates are too low for this to be a primary factor. Selection may have maintained many favorable new mutations by protecting them from the normal process of
              attrition due to drift.

              Another possible source of the unique diversity found in cattle in NCE is historical gene flow from an as yet unidentified origin. Two candidates for this source are local wild aurochs (Bos primigenius), which persisted in NCE until the sixteenth century, and domestic cattle other than those that gave rise to present day European cattle (outside NCE). Extensive wild auroch introgression seems unlikely, and no mtDNA sequences have been detected in European cattle which match aurochs sequences identified using ancient DNA
              sequencing.

              Notably, our findings contradict the results of previous surveys of genetic variation in European cattle which suggested that diversity declines with distance from the Fertile Crescent region. This discrepancy could be explained by human selection on the milk genes, and it may also reflect different sampling strategies. Our analysis is based
              on a sample set that is unprecedented in size, geographic coverage and breed diversity. Furthermore, unlike previous studies, we analyzed only nonsynonymous polymorphisms in
              strong candidate genes most likely to yield unusual geographic patterns in milk gene diversity.

              Our study provides evolutionary insights and identifies high diversity in cattle genes that are economically important, suggesting that cattle in NCE are a potentially precious
              genetic resource for future agricultural productivity.

              Farming practices since the Neolithic seem to have left reciprocal genetic signatures in cattle and human populations from NCE. This may represent a rare example of cultural-genetic coevolution between humans and another
              species. Other examples of coevolution have been documented for human genes and genes of parasites, such as Plasmodium14. But our study represents the first non-disease-related example of genetic coevolution between
              humans and domestic animals, reflecting the extent to which domestication has shaped human societies and the genomes of
              both humans and cattle. END.




              When did the LP migrations begin?

              Paper B.
              Nigel Calder early summarised the extant archaeologic, genetic and linguistic features of the spread of LP in his book "Timescale" (1983, Viking Press) isbn-0-670-71571-9p207 et seq.



              1.Dairymen. (milk-drinking proto-Semitic speakers with milking cows and plows (6000 ybp) moved from the steppe fringe of the Fertile Crescent into Egypt, and across the Sahara Desert, arriving in Western Africa 4500 ybp; also into southern Mesopotamia, where the Semitophone empire of Akkad emerged 4400 ybp,.

              2.Horsemen (milk-drinking proto-Indo-European speakers with milking cows and tamed horses) 4900ybp moved from the lower Volga River into semi-arid niches in southwestern Asia and across the Eurasian steppes; into Anatolia as the Luvians (4900 ybp),; before that into southern Greece (4350ybp); the technology reached into western Europe (France, Ireland) by 4300 ybp

              3.An anachronistic later deposition of LP type archaeology correlates with the northern Hittite ( IE-speaker) civilization. (4000ybp).
              { ? A niche incursion after a non-LP depopulation.} END.

              >{Comment: More detailed genomic works now being displayed provides closer focus on parts of the story. They indicate patchy ancient LP distribution despite a "swift" deposition of distributed samples of the symbiotic culture across Europe.
              Swift? Well, the Steppes to Ireland in under 2000 years, about 20 miles per generation, just sufficient for the lusty adolescents to find independence from the parents, but still near enough to visit. }

              Food for further thought?

              Comment

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