investigator studying the Y chromosome of a 49,000 - class - old Neanderthal from Spain unveil that it ’s unlike that of any humans today . Prehistoric femaleHomo sapiensmay have been genetically antagonistic with the virile Neanderthals they matt-up with . The deviation in Y chromosomes may have chair to the stillbirth of hybrid male fetuses , harmonize to determination published in theAmerican Journal of Human Geneticsthis week .
Because humans today carry trace of Neanderthal DNA , we sleep together that Neanderthals mixed with anatomically forward-looking humans who exposit out of Africa . However , " we ’ve never observe the Neanderthal Y chromosome DNA in any human sampling ever test , " Stanford’sCarlos Bustamantesaid in astatement . " That does n’t leaven it ’s entirely extinct , but it in all likelihood is . "
Bustamante , together with a squad precede by Stanford’sFernando Mendez , psychoanalyze the Y - chromosome desoxyribonucleic acid of a Neanderthal male from El Sidrón , Spain . They also compared it to cite sequences of chimpanzee and innovative human Y chromosomes . Although the Neanderthal Y chromosome ( and the motherly inherit mtDNA ) might have just drifted out of the modern human gene kitty , it ’s also possible that genetic incompatibility contributed to the going .
The squad chance potentially prejudicious changes to four factor on the Neanderthal Y chromosome : PCDH11Y , TMSB4Y , USP9Y , and KDM5D. The first three are unequalled to the Neanderthal stock , while the fourth is found in modern human sequence , and it put one across for an enzyme that suppress the invasiveness of some cancers . Male - specific antigens gain from KDM5D may enkindle an resistant response in pregnant women against the manful fetuses they ’re carrying – which could lead in a abortion .
Additionally , the squad also found that the Neanderthal Y chromosome from El Sidrón diverge from that of innovative homo around 588,000 years ago . Their estimate of Y - chromosome divergence fit with previous work on the population divergence of Neanderthals and our human ancestors .
Neanderthal Y - chromosome genes likely go away from the human genome a foresightful time ago , and it ’s possible that incompatibilities at one or more of those genes keep these twoHomogroups reproductively isolated . " The functional nature of the mutations we found suggests to us that the Y chromosome may have played a role in barrier to cistron flow , " Bustamante added . The team plans to transmit experiments to demonstrate this .
