November 24, 2006 | David F. Coppedge

Genetic Study Points to Three Ancestral Families of Humans

In a paper just published in Nature,1 scientists mapped the DNA of 270 people from four people groups: European, African, Chinese, and Japanese.  The scientists were looking for sections of DNA that are either missing or duplicated.  Many sections of our DNA appear over and over again.  The number of extra copies varies between individuals and between people groups.  The number of copies is called the Copy Number Variation (CNV).
    The major excitement in their study was the finding of a link between locations within chromosomes of DNA that are missing or duplicated and the locations on the chromosomes of many diseases.  DNA code that scientists used to call useless junk, left over from the random process of evolution, are now turning out to contain mechanisms that determine many physical characteristics and control much of our body chemistry.  A whole new field of research is opening up:

Our map of copy number variation in the human genome demonstrates the ubiquity and complexity of this form of genomic variation.  The abundance of functional sequences of all types both within and flanking areas of copy number variation suggests that the contribution of CNVs to phenotypic variation is likely to be appreciable.  This prediction is underscored by the impact of copy number variation on variation in gene expression.

Buried in the report was the observation that although their samples came from four geographical areas, the samples divided themselves neatly into three distinct groups.  The Chinese and Japanese fell into the same group, with the Europeans and Africans being the other two:

“In contrast to other classes of human genetic variation, the population genetics of copy number variation remains unexplored.  The distribution of copy number variation within and among different populations is shaped by mutation, selection and demographic history….To demonstrate the utility of copy number variation genotypes for population genetic inference we performed population clustering on 67 genotyped biallelic CNVs.  We obtained the optimal clustering with the assumption of three ancestral populations, with the African, European and Asian populations clearly differentiated.

Click here for a striking graph of how sharply the three groups are separated.  The legend on the graph denotes people groups: Nigeria (YRI), Europe (CEU), Japan (JPT) and China (CHB).


1Redon et al, “Global variation in copy number in the human genome,” Nature 444, 444-454 (23 November 2006) | doi:10.1038/nature05329.
See also: BBC News, National Geographic and News@Nature.

Although this study considered only a limited sample, this is either a remarkable coincidence or confirmation of the biblical account in Genesis 9 to 11 describing all the peoples of the earth coming from the three sons of Noah.  Further studies should confirm with larger numbers of samples from more locations that all the world’s population can be separated into three groups.
    How will this affect the popular “Out of Africa” theory of man’s origin?  Further research could create quite a lot of stress among anthropologists whose careers are based on the “Out of Africa” story.  What new tale will evolutionists come up with to account for three ancestral populations?
    Not surprisingly, the major news media, such as the BBC, had practically nothing to say about there being only three ancestral populations, focusing rather on the medical aspects of the paper.  A review of the paper by Physorg, however, jumps to the defense:

Evolution is another area that will come under new scrutiny.  The “Out of Africa” scenario, by which Homo sapiens emerged from east Africa and spread around the globe, will not be challenged, though.  Our origins are so recent that the vast majority of CNVs, around 89 percent, was found to be shared among the 269 people who volunteered blood as samples for the study.  These individuals included Japanese from Tokyo, Han Chinese from Beijing, Yoruba from Nigeria and Americans of Northern and Western European ancestry.  All the same, there are widespread differences in CNVs according to the three geographical origins of the samples.  This implies that, over the last 200,000 years or so, subtle variants have arisen in the genome to allow different populations of humans adapt to their different environments, Wellcome Trust Sanger said in a press release.

So it sounds like “Out of Africa” is safe.  All we are asked to believe is that in the course of 200,000 imaginary years, or perhaps 10,000 generations, there has been so little mixing of the gene pool that we still see three very distinct groups.  This could be a problem.  We are still left with the requirement that at some point in the past, say about 200,000 imaginary years ago (or perhaps only 3400 years ago) there was a time when the human population, for some unexplained reason, shrank to the point that it was able to form three distinct genetic groups.  Sorry, but this is still sounding a lot like the three sons of Noah.
—DK

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Categories: Early Man, Genetics

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