tag:blogger.com,1999:blog-7785493.post7977169596045980086..comments2024-01-04T04:11:55.717+02:00Comments on Dienekes’ Anthropology Blog: Y-chromosomes and coronary artery disease in BritainDienekeshttp://www.blogger.com/profile/02082684850093948970noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-7785493.post-78654169089849986932012-02-11T18:24:23.546+02:002012-02-11T18:24:23.546+02:00This might help to explain why R1b is so common in...This might help to explain why R1b is so common in western Europe while being apparently very young. If R1b had a genetic advantage over Haplogroup I then natural selection would have favored the R1b carriers.Average Joehttps://www.blogger.com/profile/12203996329459638052noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-79796941348474949882012-02-10T18:54:38.624+02:002012-02-10T18:54:38.624+02:00The differential expression piece does support non...The differential expression piece does support non-neutral NRY-DNA but, in general, it is appropriate to clearly rule out the possibility that social class/cultural practices that happen track to ancestry informative genetic information.<br /><br />As an intentionally unrealistic and exaggerated example to illustrate the idea, if eating Haggus is an immense risk factor for heart disease and Scots are disproportionately Y-DNA I due to their demographic history as a people, then it could look like Y-DNA was causing effects that were really due to diet.<br /><br />On the other hand, there is no reason that Y-DNA shouldn't have selective effects, and indeed, since it is the only uniparental marker in the ordinary genome (as opposed to the mitchondrial genome) and is the place where adapations that are selectively fitness enhancing in men but reduce selective fitness in women are most favored, one would expect there to be selectively non-neutral alleles in Y-DNA (although I'm inclined to think that the individual level selection effects on Y-DNA have probably swamped by the group selection effects on Y-DNA since the Neolithic - coronary artery disease, for example, had very little impact on selective fitness until the germ theory of disease and accompanying hygene measures, vaccines, antibiotics, and improved diet quality and consistency dramatically reduced the importance of other selective factors that swamped the relevance of coronary artery disease (which typically strikes only once one has had children who are at least adolescents, if not adults by the time it strikes and which is typically not a visible factor in choice of mate or in pre-death economic success).<br /><br />A plausible heuristic and hypothesis to explain the difference would be that Y-DNA I may reflect pre-Neolithic hunting and gathering lifestyles when the wild meats they ate were leaner and there were more low cholesterol nuts as protein sources in their diets, while R1b1b2 may have adaptations that thrived in the Neolithic or later that involved higher fat diets associated with eating livestock.Andrew Oh-Willekehttps://www.blogger.com/profile/02537151821869153861noreply@blogger.com