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Thread: Lactase Persistence Over the Last 3,000 Years

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    1 members found this post helpful.
    R1b-V88 did pick up pastoralism in the Balkans ca 8 ka, 200 years after farmers from Anatolia arrived in that area
    whether they had developped lactase persistence, I don't know but that seems to early to me
    however, if the farmers from Anatolia had lactase persistence, R1b-V88 would have inherited it too, as they mixed with farmers daughters

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    Lactase persistence and 13910*T in Iran:


    The evolutionary genetics of lactase persistence in seven ethnic groups across the Iranian plateau (Charati et al. 2019)

    "The LP (lactase persistence) frequency distribution ranged from 0 to 29.9% in the seven Iranian ethnic groups with an average value of 9.8%. The variants, − 13910*T and − 22018*A, were significantly associated with LP phenotype in Iranians. (...) Our results indicate the distribution of LP in seven ethnic groups across the Iranian plateau. Soft selective sweep rather than hard selective sweep played a substantial role in the evolution of LP in Iranian populations. (...)

    The recent genetic screening for Iranians showed the occurrence of − 13910*T at 10%
    . The genotype-phenotype correlation was high, suggesting that − 13910*T might explain LP in Iranian population (…) The prevalence of − 13910*T was found in most populations (4.16–7.69%) with the exception of the Gilaks. (...)


    All − 13910*T alleles were observed on haplotype A that is agreement with previous studies. (...)

    In particular, the occurrence of − 13910*T in two distinguished LP haplotypes was observed in Iranians. Both haplotypes in Iranians were dated within 3000 years that was much later than the dairying practices spread from the West Asia to Europe, raising the possibility that the − 13910*T alleles might be introduced into Iran recently."

    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6371433/
    Last edited by Philjames100; 04-08-20 at 20:26.

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    Lactase persistence and 13910*T in India:


    Herders of Indian and European Cattle Share Their Predominant Allele for Lactase Persistence (Romero et al. 2012)

    “we sought to determine whether lactase persistence has evolved independently in the Indian subcontinent. Here, we present the results of the first comprehensive survey of the LCT enhancer region in south Asia. Having genotyped 2,284 DNA samples from across the Indian subcontinent, we find that the previously described west Eurasian -13910 C>T mutation accounts for nearly all the genetic variation we observed in the 400- to 700-bp LCT regulatory region that we sequenced. Geography is a significant predictor of -13910*T allele frequency, and consistent with other genomic loci, its distribution in India follows a general northwest to southeast declining pattern, although frequencies among certain neighboring populations vary substantially. We confirm that the mutation is identical by descent to the European allele and is associated with the same >1 Mb extended haplotype in both populations. (...)

    the derived -13910*T allele has the highest frequency among the observed mutations as well as the widest distribution throughout the Indian subcontinent. Its frequency ranges from 0.8% among the Tibeto-Burman speakers to 18.4% among Indo-European speakers, with west India showing the highest frequency of the derived allele; it has an average countrywide frequency of 10.3%. (...)

    We grouped populations by their linguistic or geographic affiliation and carried out Kruskal–Wallis tests to assess the effect of these factors on -13910*T allele frequencies. Both geography and language exhibit significantly nonrandom association with allelic frequencies, whereby groups from west India, or those that speak Indo-European languages are more likely to carry the -13910*T allele than any other group. It is difficult to quantify the degree of autocorrelation between our two main explanatory variables, but they are well known to covary; a further Kruskal–Wallis test applied only on data from Indo-European speakers showed that geography remains significant even when controlling for language. (...) at a countrywide level pastoralism is significantly associated with elevated frequencies of -13910*T (...)

    a key question is whether the Indian -13910*T allele is identical by descent to the European one or the product of convergent evolution. … All -13910*T alleles in our southern Asian sample are found on the previously defined European A haplotype background, strongly arguing for a single common origin. (...)

    Indo-European–speaking groups were repeatedly identified as being significantly associated with lactase persistence in our data (...)

    Population-level -13910*T allele frequencies within our samples range from 0 to 0.489 (48.9%) (...)


    Short- and long-range haplotype data point strongly toward a single shared origin of the -13910 C>T mutation in Europe and India. Given the distribution of the -13910*T allele, the observed degree of haplotype conservation indicates a recent origin followed by a rapid rise in frequency, most likely driven by strong positive selection.

    Comparison of the European and Indian history of cattle keeping suggests that the context for the selective sweep was in place in Europe roughly 2,000 years earlier than in south Asia (...) It is therefore plausible that from Europe, the allele subsequently spread into Central Asia, the Near East, Pakistan, and India (...)

    Interestingly, a similar small-scale introgression event may also explain the presence of the 13910*T allele in central African populations. The overall low frequency of the -13910*T allele in the subcontinent, and its absence from roughly a third of the population samples, suggests that the selective advantage it confers has been largely restricted to pastoralist groups. Three of the five sampled pastoralist populations have -13910*T allele frequencies vastly greater than the sample mean; of those, the Ror of Haryana are responsible for the frequency peaks visible in figure 1, a pattern suggestive of adaptation to a lifestyle tightly associated with the consumption of milk products by these populations.

    Populations from north or west India that speak Indo-European languages have, in general, substantially higher frequencies of the -13910*T allele than Dravidian speakers from the south. ... and within the Indo-European speaking groups, there is a clear west to east frequency decline ... This geographically contiguous patterning of variation in the locus is consistent with other genetic data from both autosomal and uniparentally inherited marker loci in India. (...)

    haplotype analyses indicate that the -13910*T allele in India is identical by descent to that found in Europe and western Asia, whereas examination of the pattern of haplotype block structure in the context of the archaeological history of herding across this intercontinental region suggests that the -13910*T allele was introduced to India from the west."


    Figure 1:




    https://academic.oup.com/mbe/article/29/1/249/1749245
    Last edited by Philjames100; 04-08-20 at 20:25.

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    I think the point is that this mutation wasn't positively selected until recently, which doesn't really tell us much about its origin. The spread is obviously linked to cultures who practiced animal husbandry. It's certainly possible, if not likely, these European cultures were rich in R1b, even if that male lineage had nothing to do originally with cattle domestication, or goat or some other milking animal..

    How did V88 get to Africa? Ancient Spain? Sardinia? Heck even ancient Syria is possible. (a sizeable V88 population exists there too)

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    Quote Originally Posted by Aaron1981 View Post
    Heck even ancient Syria is possible. (a sizeable V88 population exists there too)
    Do you have any more info on that?

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    Quote Originally Posted by Aaron1981 View Post
    Heck even ancient Syria is possible. (a sizeable V88 population exists there too)
    do you know what subclades?

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    So what was dairy consumption like back then?

    -yogurt?
    -strained yogurt?
    -milk?
    -cheese?
    -cream?
    -clotted cream?
    -butter?

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    Nice information

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    Quote Originally Posted by ratchet_fan View Post
    So what was dairy consumption like back then?

    -yogurt?
    -strained yogurt?
    -milk?
    -cheese?
    -cream?
    -clotted cream?
    -butter?
    Good question

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    Toubou DNA:


    Chad Genetic Diversity Reveals an African History Marked by Multiple Holocene Eurasian Migrations (Haber et al. 2016)

    “the Toubou have 20%–30% Eurasian ancestry (…) Previous studies have suggested that the Eurasian backflow into East Africa came from a population related to early Neolithic farmers. We wanted to know whether the Eurasian ancestry we found in the Toubou can be traced to the same source populations … the most significant result was for present-day Sardinians. … early Neolithic farmers were the most significant contributors (…) Among modern populations, Sardinians showed the highest genetic affinity to both the Toubou ... Ancient Eurasians also showed correlated affinity to both the Toubou... the early Neolithic LBK (Linearbandkeramik, or Linear Pottery) population (∼5,000 BCE) had the highest affinity. (...)

    (in the Toubou) we found signals of selection on MCM6 rs4988235 (13910*T), a variant associated with the lactase-persistence phenotype (ability to digest milk). This SNP was previously found to be under strong positive selection in Europeans, where it was probably advantageous to individuals living in pastoralist societies. The frequency of this variant in the Toubou is 2%… Although this SNP appears to be a candidate for selection, we suggest that it has probably drifted neutrally in the Toubou after the Eurasian gene flow: the Toubou have ~30% Eurasian ancestry from a population similar to the Greeks, who have 13% derived alleles at rs4988235, suggesting an expectation of ~3.9% of the derived allele simply from admixture. We similarly found in the Toubou signals at HERC2 rs1129038 a major contributor to blue eye color in Europeans, as well as a signal at SLC24A5 rs1834640, a major contributor to (light) pigmentation.”

    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5142112/


    “We find in Chad a high frequency of Y-haplogroup R1b (R1b-V88) in all ethnic groups examined. … We also find the Eurasian haplogroup T (T1a) in Toubou with Toubou having a high frequency (31%) of their studied males belonging to this haplogroup… instances of this haplogroup in examined ancient populations are in the Linearbandkeramik (LBK) population which we found to be the most significant reference for the Eurasian ancestry in Toubou”

    (Haber et al, 2016 supplementary material)


    Is there actually any close relationship between the T1a found in the Toubou and in the Linearbandkeramik?


    Fulani also have about 18% Y-DNA T1a.

    https://en.wikipedia.org/wiki/Fula_people#Genomic_studies
    https://en.wikipedia.org/wiki/Haplogroup_T-M184#Africa
    https://www.eupedia.com/europe/Haplogroup_T_Y-DNA.shtml


    "there are 119 lineages in the macro-haplogroup K-M9 (which includes haplogroups K1-K4 and L to T). Of these lineages, only two have been observed in sub-Saharan Africa at appreciable frequencies: T-M70 (T1a) and R-V88 (R1b-V88)"

    Cruciani et al. 2010


    This connection between R1b-V88 and T1a is very interesting. As far as I'm aware the only ancient culture in which R1b-V88 and T have been found together so far is the Varna culture, in Bulgaria (4500 BC).





    "The numerous archaeological materials [in the Varna necropolis] make it possible to try to explain some aspects of the spiritual culture of the time. … When comparing the stock of grave 43 (a rich grave containing the skeleton of a man) and other collected data, we could suggest that the symbolic graves of this type are designed either as a glorification of the dead or as a cult of the ancestors – founders of the clan and tribe. That the god is a man is judged by the presence of a sceptre and some typically male in function objects… In this grave the prevailing part of the finds implies that the god could be that of stock-breeding. The main evidence for this are the two animal figurines and 30 heads of animals made of flat gold plates.”

    Ivanov 1982 p.21

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    More info on lactase persistence in Africa:


    Sahelian pastoralism from the perspective of variants associated with lactase persistence (Priehodová et al. 2020)



    Abstract

    Objectives: Archeological evidence shows that first nomadic pastoralists came to the African Sahel from northeastern Sahara, where milking is reported by 7.5 ka. A second wave of pastoralists arrived with the expansion of Arabic tribes in 7th–14th century CE. All Sahelian pastoralists depend on milk production but genetic diversity underlying their lactase persistence (LP) is poorly understood. Materials and methods: We investigated SNP variants associated with LP in 1,241 individuals from 29 mostly pastoralist populations in the Sahel. Then, we analyzed six SNPs in the neighboring fragment (419 kb) in the Fulani and Tuareg with the −13910*T mutation, reconstructed haplotypes, and calculated expansion age and growth rate of this variant.

    Results: Our results reveal a geographic localization of two different LP variants in the Sahel: −13910*T west of Lake Chad (Fulani and Tuareg pastoralists) and −13915*G east of there (mostly Arabic-speaking pastoralists). We show that −13910*T has a more diversified haplotype background among the Fulani than among the Tuareg and that the age estimate for expansion of this variant among the Fulani (8.5 ka) corresponds to introduction of cattle to the area.

    Conclusions: This is the first study showing that the “Eurasian” LP allele −13910*T is widespread both in northern Europe and in the Sahel; however, it is limited to pastoralists in the Sahel. Since the Fulani haplotype with −13910*T is shared with contemporary Eurasians, its origin could be in a region encompassing the Near East and northeastern Africa in a population ancestral to both Saharan pastoralists and European farmers.


    Link








    Excerpts:

    Although the auroch, ancestor of the domestic cattle, also lived in northeastern Africa, as evidenced by rock art and archeological findings, its domestication took place in Asia. The auroch was domesticated independently in the Near East and in India and two different breeds were subsequently introduced to Africa. (...) In sub-Saharan Africa and Arabia, the first food-producing societies were nomadic pastoralists. (...)

    Several variants associated with LP are found in current populations. There are three different mutations in eastern Africa (−14010*C, −14009*G, and −13907*G), one in western Eurasia and northwestern Africa (−13910*T), and one in Arabia and northeastern Africa (−13915*G). These mutations can be viewed as evidence of convergent genetic adaptation of humans to pastoralism. It has been estimated that allele −13910*T is the oldest among these variants. Simulation models show that it emerged somewhere between central Europe and northern Balkans at 7.5 ka, but its presence has not yet been attested by ancient DNA studies of European human remains from this period. Currently the prevailing view is that this allele had been present in the population at a very low frequency and became strongly selected for much later, perhaps during the Bronze Age, in conjunction with other alleles associated with lipid metabolism.

    As mentioned above, the −13910*T variant occurs not only in western Eurasia but also in northwestern Africa. Based on high frequencies of −13910*T and Eurasian Y chromosome haplotypes in the Fulani (Fulbe) from Cameroon, it has been suggested that this LP variant may have been introduced in their population from outside Africa. Based on (probably different) Fulani DNA samples but again from northern Cameroon, it has been demonstrated that their −13910*T variant shares its haplotype backgrounds with Europeans, which suggests a single mutation event for this mutation and its introduction via admixture of non-African sources and through gene flow. A recent study of Fulani pastoralists from Ziniaré, Burkina Faso (Vicente et al., 2019) confirmed these suggestions and showed that this variant shares its haplotype background with Eurasians and that ancestors of the Fulani probably acquired the haplotype via recent admixture events which took place in northern Africa. (...)

    We screened the sequences for five variants (−13907*G, −13910*T, −13915*G, −14009*G, and −14010*C) associated with LP. The most frequent variant in our dataset, −13910*T, was found in all analyzed western Sahelian pastoralists such as the Fulani, Tuareg, and Moors in more or less similar frequencies but was not present in other groups. The second most widespread variant in our dataset, −13915*G, was found in seven populations living in the eastern part of the region. It occurred at the highest frequency among the Kababish Arabs (33.3%), while in other populations, its frequency was rather low. The third most frequent variant was −14009*G, found almost exclusively among the Beja (42.6%): in other groups, it was present at much lower frequencies. Variant −13907*G was found in seven Afar, five Beja, and one Kababish individual, and variant −14010*C was not found in our dataset at all. The LP variants of the Sahelian and neighboring populations are shown in Figure 1. (...)

    Using the method of Austerlitz et al. (2003), we estimated the expansion age of −13910*T in the Fulani population at 7,534–9,686 ya, along with a slow growth rate of 1.033–1.053. (...)


    Discussion

    Our investigation of LP variant frequencies revealed new and interesting results related to the origins of pastoralism and subsequent gene flow between pastoralists and farmers in the Sahel/Savannah belt of Africa. We observed a clear distinction between regions west and east of Lake Chad: while variant −13910*T prevails in the western Sahel, where we found it only in pastoralists such as the Fulani, Tuareg, and Moors (it is virtually absent in sedentary farmers analyzed in our dataset), eastern Sahel appears to be much more diverse and several LP-associated variants, such as −13907*G, −13915*G, and 14010*C, are found in various populations.

    The −14009*G variant has been associated with LP in eastern Africa (Jones et al., 2013; Jones et al., 2015) and frequency at which we found it in the Beja near Kassala, Sudan (42.6%) is much higher than reported by other studies. (...)

    Our study shows that the age of expansion of −13910*T obtained for the Fulani pastoralists in western Sahel/Savannah belt (7,534–9,686 years ago) is much older than that obtained for the −13915*G in Arabic pastoralists in eastern Sahel/Savannah belt, when applying the same method. Priehodová et al., 2017 estimated age of −13915*G at between 1,274 and 1,782 years ago, which is consistent with the time of Arabic expansion to Africa. The estimate obtained in this study for the Fulani pastoralists conforms to estimates for introduction of pastoralism in Africa which are based on archeological evidence. (...)

    This first Saharan/Sahelian influx of population with LP individuals was followed by a later migration of other pastoralists from the Arabian Peninsula throughout northern Africa and Sahara up to the Lake Chad Basin, which was led by Bedouin Arabic-speaking tribes. This migration probably introduced the −13915*G variant to the region, which originated in Arabia as an adaptation to the consumption of camel milk. (...)

    It has been suggested that the Fulani acquired the −13910*T haplotype by admixing with a North African population which had some Eurasian ancestry, so that this variant in the Fulani population has the same descent as the variant found in Eurasia. Furthermore, it has been estimated that two distinct admixture events took place, one 1,828 and the other 302 years ago (Vicente et al., 2019). Our estimates of the growth and selection of −13910*T haplotype in the Fulani indicate an earlier dating than the above mentioned admixture times (Vicente et al., 2019) and are consistent rather with the estimates of Coelho et al. (2005), who proposes a period of 10,125–6,060 years ago.

    The age of the second main LP Sahelian variant −13915*G, which we estimated at 1.5 ka, perfectly matches the timing of migration of Bedouin tribes from Arabia to Africa. A previous estimate of the age of −13915*G, which was up to 4 ka (Enattah et al., 2008), concerns its origin in Arabia, probably Central Arabia. From there, it expanded at the beginning of Middle Ages, therefore much later than the −13910*T variant, which was already established in the western Sahelian populations.

    This discrepancy between the age estimates of −13910*T in the Fulani population can be explained by the fact that the two studies, that is, our present study and Vicente et al.'s (2019), targeted different parts of the genome (a local haplotype age of growth estimate vs. a genome-wide estimate of admixture), used different dating methods, and the samples on which they were based covered different populations. Moreover, Vicente et al. (2019) analyzed only one Fulani population (from Ziniaré, Burkina Faso), while our results are based on a larger Fulani dataset stretching geographically from Senegal to Chad. Nevertheless, we want to stress that our results do not exclude the possibility of a later admixture and introgression as suggested by Vicente et al., 2019. In fact, the TAS2R genes alleles may have also been introduced to the Fulani via recent admixture with a Eurasian population (Triska et al., 2015). In short, these results reflect the complexity of the population history of Africa. (...)

    Because the −13910*T haplotype associated with LP is shared between the Fulani from Ziniaré, Burkina Faso, and Europeans (Vicente et al., 2019) and since we found an old age of expansion for this mutation within the African population of the Fulani (dataset covering much larger area of the Sahel), it is possible that the −13910*T may have originated in a food-producing population that lived in the Near East, including northeastern Africa, as suggested by Myles et al. (2005). Subsequently, though, the first Neolithic farmers who lived in the Near East/northeastern Africa were replaced by various population movements (Černý, Čížková, Poloni, Al-Meeri, & Mulligan, 2016; Vyas et al., 2016), with the result that only the originally “Arabian” –13,915*G LP variant is present in this region today (Priehodová et al., 2014). (...)

    Interestingly, genetically the nearest population to the first Near Eastern farmers has been conserved in Sardinia (Chiang et al., 2018; Sikora et al., 2014), where the frequency of −13910*T is as low as elsewhere in the Mediterranean (Gerbault, 2013; Meloni et al., 2001). (...)

    later migrations between Arabia, Near East, and North Africa (Černý et al., 2016; Fernandes et al., 2015) may be responsible for the fact that variant −13910*T is almost entirely absent from the Near East today (Gerbault et al., 2011)"
    Last edited by Philjames100; 13-10-20 at 10:46.

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    Quote Originally Posted by Philjames100 View Post
    More info on lactase persistence in Africa:


    Sahelian pastoralism from the perspective of variants associated with lactase persistence (Priehodová et al. 2020)



    Abstract

    Objectives: Archeological evidence shows that first nomadic pastoralists came to the African Sahel from northeastern Sahara, where milking is reported by 7.5 ka. A second wave of pastoralists arrived with the expansion of Arabic tribes in 7th–14th century CE. All Sahelian pastoralists depend on milk production but genetic diversity underlying their lactase persistence (LP) is poorly understood. Materials and methods: We investigated SNP variants associated with LP in 1,241 individuals from 29 mostly pastoralist populations in the Sahel. Then, we analyzed six SNPs in the neighboring fragment (419 kb) in the Fulani and Tuareg with the −13910*T mutation, reconstructed haplotypes, and calculated expansion age and growth rate of this variant.

    Results: Our results reveal a geographic localization of two different LP variants in the Sahel: −13910*T west of Lake Chad (Fulani and Tuareg pastoralists) and −13915*G east of there (mostly Arabic-speaking pastoralists). We show that −13910*T has a more diversified haplotype background among the Fulani than among the Tuareg and that the age estimate for expansion of this variant among the Fulani (8.5 ka) corresponds to introduction of cattle to the area.

    Conclusions: This is the first study showing that the “Eurasian” LP allele −13910*T is widespread both in northern Europe and in the Sahel; however, it is limited to pastoralists in the Sahel. Since the Fulani haplotype with −13910*T is shared with contemporary Eurasians, its origin could be in a region encompassing the Near East and northeastern Africa in a population ancestral to both Saharan pastoralists and European farmers.


    Link








    Excerpts:

    Although the auroch, ancestor of the domestic cattle, also lived in northeastern Africa, as evidenced by rock art and archeological findings, its domestication took place in Asia. The auroch was domesticated independently in the Near East and in India and two different breeds were subsequently introduced to Africa. (...) In sub-Saharan Africa and Arabia, the first food-producing societies were nomadic pastoralists. (...)

    Several variants associated with LP are found in current populations. There are three different mutations in eastern Africa (−14010*C, −14009*G, and −13907*G), one in western Eurasia and northwestern Africa (−13910*T), and one in Arabia and northeastern Africa (−13915*G). These mutations can be viewed as evidence of convergent genetic adaptation of humans to pastoralism. It has been estimated that allele −13910*T is the oldest among these variants. Simulation models show that it emerged somewhere between central Europe and northern Balkans at 7.5 ka, but its presence has not yet been attested by ancient DNA studies of European human remains from this period. Currently the prevailing view is that this allele had been present in the population at a very low frequency and became strongly selected for much later, perhaps during the Bronze Age, in conjunction with other alleles associated with lipid metabolism.

    As mentioned above, the −13910*T variant occurs not only in western Eurasia but also in northwestern Africa. Based on high frequencies of −13910*T and Eurasian Y chromosome haplotypes in the Fulani (Fulbe) from Cameroon, it has been suggested that this LP variant may have been introduced in their population from outside Africa. Based on (probably different) Fulani DNA samples but again from northern Cameroon, it has been demonstrated that their −13910*T variant shares its haplotype backgrounds with Europeans, which suggests a single mutation event for this mutation and its introduction via admixture of non-African sources and through gene flow. A recent study of Fulani pastoralists from Ziniaré, Burkina Faso (Vicente et al., 2019) confirmed these suggestions and showed that this variant shares its haplotype background with Eurasians and that ancestors of the Fulani probably acquired the haplotype via recent admixture events which took place in northern Africa. (...)

    We screened the sequences for five variants (−13907*G, −13910*T, −13915*G, −14009*G, and −14010*C) associated with LP. The most frequent variant in our dataset, −13910*T, was found in all analyzed western Sahelian pastoralists such as the Fulani, Tuareg, and Moors in more or less similar frequencies but was not present in other groups. The second most widespread variant in our dataset, −13915*G, was found in seven populations living in the eastern part of the region. It occurred at the highest frequency among the Kababish Arabs (33.3%), while in other populations, its frequency was rather low. The third most frequent variant was −14009*G, found almost exclusively among the Beja (42.6%): in other groups, it was present at much lower frequencies. Variant −13907*G was found in seven Afar, five Beja, and one Kababish individual, and variant −14010*C was not found in our dataset at all. The LP variants of the Sahelian and neighboring populations are shown in Figure 1. (...)

    Using the method of Austerlitz et al. (2003), we estimated the expansion age of −13910*T in the Fulani population at 7,534–9,686 ya, along with a slow growth rate of 1.033–1.053. (...)


    Discussion

    Our investigation of LP variant frequencies revealed new and interesting results related to the origins of pastoralism and subsequent gene flow between pastoralists and farmers in the Sahel/Savannah belt of Africa. We observed a clear distinction between regions west and east of Lake Chad: while variant −13910*T prevails in the western Sahel, where we found it only in pastoralists such as the Fulani, Tuareg, and Moors (it is virtually absent in sedentary farmers analyzed in our dataset), eastern Sahel appears to be much more diverse and several LP-associated variants, such as −13907*G, −13915*G, and 14010*C, are found in various populations.

    The −14009*G variant has been associated with LP in eastern Africa (Jones et al., 2013; Jones et al., 2015) and frequency at which we found it in the Beja near Kassala, Sudan (42.6%) is much higher than reported by other studies. (...)

    Our study shows that the age of expansion of −13910*T obtained for the Fulani pastoralists in western Sahel/Savannah belt (7,534–9,686 years ago) is much older than that obtained for the −13915*G in Arabic pastoralists in eastern Sahel/Savannah belt, when applying the same method. Priehodová et al., 2017 estimated age of −13915*G at between 1,274 and 1,782 years ago, which is consistent with the time of Arabic expansion to Africa. The estimate obtained in this study for the Fulani pastoralists conforms to estimates for introduction of pastoralism in Africa which are based on archeological evidence. (...)

    This first Saharan/Sahelian influx of population with LP individuals was followed by a later migration of other pastoralists from the Arabian Peninsula throughout northern Africa and Sahara up to the Lake Chad Basin, which was led by Bedouin Arabic-speaking tribes. This migration probably introduced the −13915*G variant to the region, which originated in Arabia as an adaptation to the consumption of camel milk. (...)

    It has been suggested that the Fulani acquired the −13910*T haplotype by admixing with a North African population which had some Eurasian ancestry, so that this variant in the Fulani population has the same descent as the variant found in Eurasia. Furthermore, it has been estimated that two distinct admixture events took place, one 1,828 and the other 302 years ago (Vicente et al., 2019). Our estimates of the growth and selection of −13910*T haplotype in the Fulani indicate an earlier dating than the above mentioned admixture times (Vicente et al., 2019) and are consistent rather with the estimates of Coelho et al. (2005), who proposes a period of 10,125–6,060 years ago.

    The age of the second main LP Sahelian variant −13915*G, which we estimated at 1.5 ka, perfectly matches the timing of migration of Bedouin tribes from Arabia to Africa. A previous estimate of the age of −13915*G, which was up to 4 ka (Enattah et al., 2008), concerns its origin in Arabia, probably Central Arabia. From there, it expanded at the beginning of Middle Ages, therefore much later than the −13910*T variant, which was already established in the western Sahelian populations.

    This discrepancy between the age estimates of −13910*T in the Fulani population can be explained by the fact that the two studies, that is, our present study and Vicente et al.'s (2019), targeted different parts of the genome (a local haplotype age of growth estimate vs. a genome-wide estimate of admixture), used different dating methods, and the samples on which they were based covered different populations. Moreover, Vicente et al. (2019) analyzed only one Fulani population (from Ziniaré, Burkina Faso), while our results are based on a larger Fulani dataset stretching geographically from Senegal to Chad. Nevertheless, we want to stress that our results do not exclude the possibility of a later admixture and introgression as suggested by Vicente et al., 2019. In fact, the TAS2R genes alleles may have also been introduced to the Fulani via recent admixture with a Eurasian population (Triska et al., 2015). In short, these results reflect the complexity of the population history of Africa. (...)

    Because the −13910*T haplotype associated with LP is shared between the Fulani from Ziniaré, Burkina Faso, and Europeans (Vicente et al., 2019) and since we found an old age of expansion for this mutation within the African population of the Fulani (dataset covering much larger area of the Sahel), it is possible that the −13910*T may have originated in a food-producing population that lived in the Near East, including northeastern Africa, as suggested by Myles et al. (2005). Subsequently, though, the first Neolithic farmers who lived in the Near East/northeastern Africa were replaced by various population movements (Černý, Čížková, Poloni, Al-Meeri, & Mulligan, 2016; Vyas et al., 2016), with the result that only the originally “Arabian” –13,915*G LP variant is present in this region today (Priehodová et al., 2014). (...)

    Interestingly, genetically the nearest population to the first Near Eastern farmers has been conserved in Sardinia (Chiang et al., 2018; Sikora et al., 2014), where the frequency of −13910*T is as low as elsewhere in the Mediterranean (Gerbault, 2013; Meloni et al., 2001). (...)

    later migrations between Arabia, Near East, and North Africa (Černý et al., 2016; Fernandes et al., 2015) may be responsible for the fact that variant −13910*T is almost entirely absent from the Near East today (Gerbault et al., 2011)"
    Very interesting. We're getting closer to the actual origin spot, and it's not where it was once thought to be.


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    So they do prefer a Near Eastern farmer population for the introduction of LP gene into the Fulani. Near East->North Africa->Westafrica, am I right ?

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    Quote Originally Posted by Anfänger View Post
    So they do prefer a Near Eastern farmer population for the introduction of LP gene into the Fulani. Near East->North Africa->Westafrica, am I right ?
    Apparently, but it doesn't appear to be based on anything. They don't even consider the idea that it could have come direct from Europe even though their distribution maps point to that.

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    Quote Originally Posted by Philjames100 View Post
    Apparently, but it doesn't appear to be based on anything. They don't even consider the idea that it could have come direct from Europe even though their distribution maps point to that.
    Maybe it is because the Fulani don't have any WHG autosomal DNA. Very surprising to me that the Fulani have that much Westeurasian DNA:

    Bildschirmfoto 2020-10-14 um 21.24.15.png

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    1 members found this post helpful.
    Quote Originally Posted by Anfänger View Post
    Maybe it is because the Fulani don't have any WHG autosomal DNA. Very surprising to me that the Fulani have that much Westeurasian DNA:

    Bildschirmfoto 2020-10-14 um 21.24.15.png
    They look it, though, imo. Even the old slave traders thought they were different from other tribes in Western Africa.

    It makes perfect sense to me that they came by way of the Levant.

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    Quote Originally Posted by Angela View Post
    They look it, though, imo. Even the old slave traders thought they were different from other tribes in Western Africa.

    It makes perfect sense to me that they came by way of the Levant.
    You are right. Some of them look quite Caucasoid:
    fulani_cleo_0049_copia_copia.jpg

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    Supplementary Fig. 2 (Liebert et al. 2017) shows the geographic distribution of the five most well established functional variants. The lactase persistence (LP) allele commonly found in Europe today (-13910*T) is also present in some North African populations though gene flow from Eurasia. However, there are several other LP gene variants specific to Africa and Arabia: −13907*G (rs41525747), −13915*G (rs41380347), −14009*G (rs869051967) and −14010*C (rs145946881).


    Liebert, A., López, S., Jones, B.L. et al., World-wide distributions of lactase persistence alleles and the complex effects of recombination and selection, Hum Genet (2017).

    https://link.springer.com/article/10...439-017-1847-y
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    Quote Originally Posted by Anfänger View Post
    Maybe it is because the Fulani don't have any WHG autosomal DNA. Very surprising to me that the Fulani have that much Westeurasian DNA

    They have WHG lineages, and other studies have identified European ancestry in them...





    "we demonstrate that the age estimates of West Eurasian uniparental haplogroups U5b and H1cb – which, in the Sahel/Savannah belt, occur more often in pastoralists (especially the Fulani) – are chronologically concordant with the introduction of livestock to the region (as documented independently by archaeological data). ...

    Inferring the geographical location of the ancestral West Eurasian population that was the source of these Holocene inputs to the present-day Sahel/Savannah uniparental gene pool can be approached from a phylogeographical perspective. … It is well attested that H1 emerged in Iberia/South Europe (Pereira et al., 2005b) … The parental lineage U5b1b1, aged 9 ka, is highly dispersed from the Saami in Scandinavia to Berbers in North Africa, indicating the Franco-Cantabrian refuge area as the most parsimonious source of late-glacial expansions of hunter-gatherers repopulating the entire region heading both north and south (Achilli et al., 2005). The most probable hypothesis is, therefore, that the U5b1b1b found in the Fulani today is derived from North African U5b1b1 ancestors. Both H1cb and U5b1b1b seem to be excellent markers of European – and not Near Eastern – ancestry inputs into the contemporary Fulani population.”

    (Kulichova et al. 2017)


    “Based on genome-wide analyses we propose that ancestors of the Fulani population experienced admixture between a West African group and a group carrying both European and North African ancestries. This admixture was likely coupled with newly adopted herding practices, as it resulted in signatures of genetic adaptation in contemporary Fulani genomes, including the control element of the LCT gene enabling carriers to digest lactose throughout their lives. (...)

    To examine which particular source population was a likely candidate for this postulated European contact, we extracted all European-like segments across the Fulani genomes. … The European-like segments showed the highest shared drift with Sardinians and French Basque populations …The identification of the specific ancestry fragments flanking European-like segments, supervised admixture and model based analyses support the view that the European ancestry in Fulani genomes is coupled to their North African component (...) Fregel and colleagues (2018) linked the diffusion of people across Gibraltar to Neolithic migrations and the Neolithic development in North Africa. This trans-Gibraltar mixed ancestry was previously observed in the Fulani mitochondrial gene-pool that links the Fulani to south-western Europe based on mtDNA haplogroups H1cb1 and U5b1b1b.”

    (Vicente et al., 2019)
    Last edited by Philjames100; 23-10-20 at 23:48.

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