Modern humans, Neanderthals share a tangled genetic history confirmed:


Valued Senior Member

In recent years, scientists have uncovered evidence that modern humans and Neanderthals share a tangled past. In the course of human history, these two species of hominins interbred not just once, but at multiple times, the thinking goes.

A new study supports this notion, finding that people in Eurasia today have genetic material linked to Neanderthals from the Altai mountains in modern-day Siberia. This is noteworthy because past research has shown that Neanderthals connected to a different, distant location—the Vindija Cave in modern-day Croatia—have also contributed DNA to modern-day Eurasian populations.

The results reinforce the concept that Neanderthal DNA has been woven into the modern human genome on multiple occasions as our ancestors met Neanderthals time and again in different parts of the world.

The study was published on March 31 in the journal Genetics.

"It's not a single introgression of genetic material from Neanderthals," says lead researcher Omer Gokcumen, a University at Buffalo biologist. "It's just this spider web of interactions that happen over and over again, where different ancient hominins are interacting with each other, and our paper is adding to this picture. This project will now add to an emerging chorus — we've been looking into this phenomenon for a couple of years, and there are a couple of papers that came out recently that deal with similar concepts."

more at link.....

the paper:

Analysis of Haplotypic Variation and Deletion Polymorphisms Point to Multiple Archaic Introgression Events, Including from Altai Neanderthal Lineage:

The time, extent, and genomic impact of the introgressions from archaic humans into ancestors of extant human populations remain one of the most exciting venues of population genetics research in the last decade. Several studies have shown population-specific signatures of introgression events from Neanderthals, Denisovans, and potentially other unknown hominin populations in different human groups. Moreover, it was shown that these introgression events may have contributed to phenotypic variation in extant humans, with biomedical and evolutionary consequences. In this study, we present a comprehensive analysis of the unusually divergent haplotypes in the Eurasian genomes and showed that they can be traced back to multiple introgression events. In parallel, we document hundreds of deletion polymorphisms shared with Neanderthals. A locus-specific analysis of one such shared deletion suggests the existence of a direct introgression event from the Altai Neanderthal lineage into the ancestors of extant East Asian populations. Overall, our study is in agreement with the emergent notion that various Neanderthal populations contributed to extant human genetic variation in a population-specific manner.
I read heaps on humans as I find it just so interesting.
So I am really happy when you post this sort of thing.
One things common to all humans but different from all other great apes is the number of chromosomes. This probably marks the split and the start of the new branch of Homo Sapiens.

Human Chromosome 2 is
a fusion of two ancestral chromosomes
Alec MacAndrew
All great apes apart from man have 24 pairs of chromosomes. There is therefore a hypothesis that the common ancestor of all great apes had 24 pairs of chromosomes and that the fusion of two of the ancestor's chromosomes created chromosome 2 in humans. The evidence for this hypothesis is very strong.
Maybe worth continuing.

Chromosome 2
Chromosome 2 is one of the twenty-three pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 2 is the second-largest human chromosome, spanning more than 242 million base pairs[5] and representing almost eight percent of the total DNA in human cells.
Chromosome 2 contains the HOXD
homeobox gene cluster.[6]
Mutations to homeobox genes can produce easily visible phenotypic changes in body segment identity, such as the Antennapedia and Bithorax mutant phenotypes in Drosophila. Duplication of homeobox genes can produce new body segments, and such duplications are likely to have been important in the evolution of segmented animals.
Humans have only twenty-three pairs of chromosomes, while all other extant members of Hominidae have twenty-four pairs.[7] (It is believed that Neanderthals and Denisovans had twenty-three pairs.)[7] Human chromosome 2 is a result of an end-to-end fusion of two ancestral chromosomes.[8][9][10]
The evidence for this includes:
  • The correspondence of chromosome 2 to two ape chromosomes. The closest human relative, the chimpanzee, has nearly identical DNA sequences to human chromosome 2, but they are found in two separate chromosomes. The same is true of the more distant gorilla and orangutan.[11][12]
  • The presence of a vestigial centromere. Normally a chromosome has just one centromere, but in chromosome 2 there are remnants of a second centromere in the q21.3–q22.1 region.[13]
  • The presence of vestigial telomeres. These are normally found only at the ends of a chromosome, but in chromosome 2 there are additional telomere sequences in the q13 band, far from either end of the chromosome.[14]
We conclude that the locus cloned in cosmids c8.1 and c29B is the relic of an ancient telomere-telomere fusion and marks the point at which two ancestral ape chromosomes fused to give rise to human chromosome 2.

IMO, this major mutation marks the creation and split of humans from the common ancestor. As described mutations like this alter the a actual growth blueprint in the DNA coding.

As the main difference between apes and man is mostly cosmetic except for one large difference, is the brain size and complexity in brain folds, it seems to me that is perfectly reasonable to assign the mutation of chromosome 2 as the cause for increased intelligence and the drift apart from our nearest relations.