Ye Zhang and Shi Huang ( The Out of East Asia model versus the African Eve model of modern human origins in light of ancient mtDNA findings, bioRxiv, Feb, 10, 2018. doi: https://doi.org/10.1101/546234) have proposed that an "Out of East Asia" (read that as "China") is a better model to explain human origin than the current "Out of Africa" theory.
I invite you to read the paper, which finds fault in the Genetic clock: "...The African Eve model assumes the molecular clock while the Asia model not. Given that the universal molecular clock is widely acknowledged to be unreal" (We have posted about the "clock" several times).
It upholds Huang's Maximum genetic diversity (MGD) hypothesis but does not explain it in this paper, however you can read Shi Huang's detailed explanation here (Shi Huang, New thoughts on an old riddle: What determines genetic diversity within and between species? Genomics, Volume 108, Issue 1, July 2016, Pages 3-10. https://doi.org/10.1016/j.ygeno.2016.01.008).
It also dismisses the Infinite-Sites Mutation Model or ISM, which states that all mutations that have occurred along the sequences since the most recent common ancestor only affect a new site; therefore no single position can mutate twice.
Out of Africa also requires the "Neutral Theory" to be applicable (Mutations can be harmful, and they take place at random and those that are selectively neutral accumulate while those that are deleterious are removed by natural selection). Huang disagrees with this theory (read more here: Genetic equidistance).
The authors find that "Our model furthermore specifically places the least differentiated haplotype R0 or R* as the ancestor of all mtDNA haplotypes, which is in contrast to the African Eve model that puts R downstream of haplotype N (Figure 1). The R0 haplotype is most common today in the Southern Chinese group in the 1000 genomes project, implicating the origin of the modern mtDNA lineage in Southern China [5]."
This is their Figure 1:
The paper concludes that: " the Out of East Asia mtDNA model is inherently more sound and self-consistent than the African Eve model due to stronger theoretical foundations and far more realistic assumptions. "
Readers of this blog are well aware of my anti-sinocentrism, I usually tend to take claims by Chinese scholars lightly, because of their "China is the center of the world viewpoint", however this paper is quite interesting though lacking more sound evidence to fully convince me.
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