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Mnemonics
06-24-2020, 10:31 PM
I've been trying to find out exactly how much Neanderthal admixture there is in a variety of African and Eurasian populations using the 1240K dataset from Reich Labs. I did this mostly to serve as a sort of "Tracer dye" for the Eurasian admixture in a variety of African Groups using South_Africa_2000BP

I'm using Vindija Chimp: X South_Africa_2000BP:: Vindija Chimp: Altai South_Africa_2000BP



alpha std. err Z (null=0)
result: Neanderthal_Vindija Chimp Somali.DG South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.013782 0.004592 3.001 9d
result: Neanderthal_Vindija Chimp Dinka.DG South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.002405 0.004292 0.560 9d
result: Neanderthal_Vindija Chimp Yoruba South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.002891 0.003486 0.829 9d
result: Neanderthal_Vindija Chimp Mota South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.008980 0.004720 1.902 9d
result: Neanderthal_Vindija Chimp Dinka.DG South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.002405 0.004292 0.560 9d
result: Neanderthal_Vindija Chimp Cameroon_SMA South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.000715 0.003902 0.183 9d
result: Neanderthal_Vindija Chimp Biaka South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.000265 0.003669 0.072 9d
result: Neanderthal_Vindija Chimp Mandenka South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.001049 0.003468 0.302 9d


result: Neanderthal_Vindija Chimp PPNB South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.031501 0.005650 5.575 9d
result: Neanderthal_Vindija Chimp Tianyuan South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.035889 0.006158 5.828 9d
result: Neanderthal_Vindija Chimp WHG South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.046918 0.004904 9.568 9d
result: Neanderthal_Vindija Chimp CHG South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.035868 0.004678 7.668 9d
result: Neanderthal_Vindija Chimp Anatolia_N South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.039269 0.004134 9.498 9d
result: Neanderthal_Vindija Chimp Natufian South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.028360 0.006696 4.235 9d
result: Neanderthal_Vindija Chimp Iberomaurusian South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.022338 0.004558 4.900 9d
result: Neanderthal_Vindija Chimp Morocco_EN South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.018169 0.013094 1.388 9d
result: Neanderthal_Vindija Chimp Israel_C South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.034131 0.004459 7.654 9d
result: Neanderthal_Vindija Chimp Iran_ChL South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.037438 0.004123 9.081 9d
result: Neanderthal_Vindija Chimp Iran_N South_Africa_2000BP : Neanderthal_Vindija Chimp Altai_Neanderthal South_Africa_2000BP 0.030890 0.005438 5.681 9d



The std errors are a bit large (+/- 0.3-0.6) for the tiny amounts of Neanderthal ancestry present in some groups but are fairly consistent with the major exception being Morocco_EN.

It is possible to use these Neanderthal percents to check if models of Eurasian admixture into certain populations are plausible.

Ex. Yoruba can be modeled as 13% Iberomaurusian so lets check if the Neanderthal admixture supports that.

NenA/NenB = Admixture Rate A<-B (%)

0.002891/0.022338 = 12.94% Iberomaurusian into Yoruba

Ex2. Somali.DG can be modeled as 38-39% Israel_C so lets check if the Neanderthal admixture allows us to show the a similar ratio in Somali.DG

NenA/NenB = Admixture Rate A<-B (%)

0.013782/0.034131 = 40.38% This percent is slightly higher than expected but that can be accounted for by the extra Neanderthal in Dinka and or Mota.