Tuesday, May 25, 2010

A sister relationship between European and an East Asian-African clade

I gave a talk on May 14, 2010 at the Institute of Paleontology and Paleoanthropology, Chinese Academy of Sciences, titled "Molecular evidence for the multiregional hypothesis of modern human origin and a sister relationship between European and an East Asian-African clade". Professor Xinzhi Wu, one of the major proponents of the multiregional hypothesis, was my host. see this website for the talk announcement:

I am working on the manuscript. The key findings are 1) for non-synonymous mutations or SNPS in 190 slow evolving genes, the greatest genetic diversity or distance was found within Europeans. In contrast, for synonymous mutations in these same genes or for mutations in non-coding regions, the greatest diversity was found in Africans, a well known result reproduced in our study. But as shown by the MGD hypothesis, only slow evolving genes that are in the linear range of accumulating mutations and not yet reaching maximum distance are informative to phylogeny. 2) the distance in slow evolving genes between Europeans and non-Europeans translates into a divergence time of ~2.4 million years, in good agreement with the first fossil of the genus homo. Thus, homo has been a single species since 2.4 million years ago, supporting the multiregional hypothesis. The largest distance between Asian and African is similar to the deepest distance within Europeans and translates to 2.16 million years of separation. The deepest distance within Asians is similar to that within Africans and corresponds to 1.86 million years of separation, well consistent with the first migration out of Africa ~1.9 million years ago. 3) Europeans show distinct SNP structure in non-synonymous SNPs from non-Europeans.

The recent Neandertal genome paper in Science, contrary to the claim by the paper, fully falsifies the out of Africa plus interbreeding model. First, the paper found Neandertal to be 4-6 times more distant to chimpanzee than extant humans are, fully supporting my earlier paper on all known informative fossil sequences (1). These authors are masters of cherry picking like most in the field and downplay this finding by stating it is due to sequencing errors. If an unexpected result is due to such errors, can one have any confidence on their other results? Second, from Figure 5a of that paper, it is shown that some fast evolving sequences shows a distance between a modern European (ref genome) and Neandertal to be, say 0.22, while a distance between two modern Europeans (the ref genome and Venter genome) to be 0.157. Since the separation between European and Neandertal according to the present paradigm is 360K years while the separation between two Europeans is at most ~60k years, given a distance of 0.22 between European and Neandertal, we would expect to see a distance of less than 0.037 between two Europeans. Well, such anomaly was simply ignored by the paper. Finally, the paper notes the striking finding that equal intermixing of Neandertals with Europeans and Asians did not translate into equal physical resemblance of Europeans and Asians to the Neandertals. Why such disconnection between genotype and phenotype? All modern molecular biology, as well as the MGD hypothesis and common sense, have repeated shown that there is an inseparable unity between genotypes and phenotypes.

So the bottom line is that the Neandertals were the ancestors of Europeans and have mostly nothing to do with Asians. We are analyzing the Neandertal genome to find direct evidence for this. The small amount 0.1-0.4% similarity of Asians with Neandertals are due to convergent evolution, just like the greater similarity between Europeans and Asians in fast evolving genes are due to the same process. Or the greater similarity between humans and chimpanzees than between humans and orangutans are due to the same process, where chimpanzees and orangutans belongs to the pongid clade to the exclusion of humans.

1. Huang, S. (2008) Ancient fossil specimens are genetically more distant to an outgroup than extant sister species are. Rivista di Biologia / Biology Forum 101: 93-108.