ed ▁ha plot ype ▁B 0 0 6 ▁of ▁the ▁d yst roph in ▁gene ▁has ▁also ▁been ▁found ▁among ▁nom ad ▁past oral ist ▁groups ▁in ▁the ▁Sah el ▁and ▁Horn ▁of ▁Africa , ▁who ▁are ▁associated ▁with ▁northern ▁populations . ▁Con sequently , ▁the ▁presence ▁of ▁this ▁B 0 0 6 ▁ha plot ype ▁on ▁the ▁northern ▁and ▁n ort he astern ▁per imeter ▁of ▁Sub - S ah aran ▁Africa ▁is ▁attributed ▁to ▁gene ▁flow ▁from ▁a ▁non - A fr ican ▁point ▁of ▁origin . ▁ ▁East ▁and ▁North ▁Asia ▁ ▁" T ian y uan ▁Man ", ▁an ▁individual ▁who ▁lived ▁in ▁China ▁c . ▁ 4 0 , 0 0 0 ▁years ▁ago , ▁showed ▁substantial ▁Ne ander th al ▁ad mi xture . ▁A ▁ 2 0 1 7 ▁study ▁of ▁the ▁ancient ▁DNA ▁of ▁T ian y uan ▁Man ▁found ▁that ▁the ▁individual ▁is ▁related ▁to ▁modern ▁Asian ▁and ▁Native ▁American ▁populations . ▁A ▁ 2 0 1 3 ▁study ▁found ▁Ne ander th al ▁intro gression ▁of ▁ 1 8 ▁gen es ▁within ▁the ▁chrom os ome ▁ 3 p 2 1 . 3 1 ▁region ▁( H Y AL ▁region ) ▁of ▁East ▁A si ans . ▁The ▁intro gress ive ▁ha plot ypes ▁were ▁posit ively ▁selected ▁in ▁only ▁East ▁Asian ▁populations , ▁rising ▁stead ily ▁from ▁ 4 5 , 0 0 0 ▁years ▁ago ▁until ▁a ▁sudden ▁increase ▁of ▁growth ▁rate ▁around ▁ 5 , 0 0 0 ▁to ▁