Neanderthals and our ancestors interbred with Neanderthals and in the process inherited 99.5 % of the same DNA. Despite strikingly similar and overlapping DNA, modern humans and Neanderthals were genetically dissimilar from each other because of a missing chromosome.

The genetic dissimilarity could have also discouraged interbreeding between the two groups.Recent research has thrown new light on the relationship between the Neanderthals and modern humans or the lack of it. Modern humans have DNA from Neanderthals indicating that we have interbred with them at some time in our evolutionary history, but there are dissimilarities.

The study has revealed that the Y chromosomes could have created conditions which could have triggered miscarriages when the two species interbred.

Neanderthals as a species lived predominantly in Europe and Asia but died out some 40,000 years ago. The genome of the Neanderthals was first decoded in 2010 when it was first revealed that humans and Neanderthals interbreed.

The study reveals that the ‘Y-chromosome’ of the Neanderthals was distinct from the humans and could trigger an immune reaction during pregnancy leading to miscarriages. According to Fernando Mendez of Stanford University and the lead researcher of the study, ‘Y-chromosome’ of the Neanderthals led to a better understanding of the divergence between the Neanderthals and modern humans.

It also opens up possibilities to explore genetic interactions ancient and modern [gene] variants within hybrid offspring.
Mendez added that the ‘Y-chromosome’ of the Neanderthals deciphered were unique and distinct from the modern day humans ‘Y’ chromosomes. It explains that the lineage in question is now extinct.

The research also revealed fascinating protein-coding differences between ‘Y-chromosome’ of the Neanderthals and the ‘Y Chromosomes’ of the modern day humans.

The study according to Mendez revealed that most of the functional difference were seen with these genes rather than the genes associated with sperm production, and this was a complete surprise.