Not all of the Neanderthal genes are beneficial. Sankararaman and Reich found that our Neanderthal inheritance includes several genes that make us susceptible to diseases including type 2 diabetes, lupus and Crohn’s disease.
Some of the genes, meanwhile, appear to have led to fertility problems. For instance, Sankararaman found that the X chromosome is almost devoid of Neanderthal DNA. This suggests that most Neanderthal DNA that wound up on the X chromosome made the bearer less fertile – a common occurrence when related but distinct species interbreed – and so it quickly disappeared from the human gene pool. “Neanderthal alleles were swept away,” says Sankararaman.
Maybe. Can we spell S-T-R-E-T-C-H?
According to another recent study,
A substantial fraction of the Neanderthal genome persists in modern human populations. A new approach applied to analyzing whole-genome sequencing data from 665 people from Europe and East Asia shows that more than 20 percent of the Neanderthal genome survives in the DNA of this contemporary group, whose genetic information is part of the 1,000 Genomes Project.
Toldjah. Some people never forgave the “Neaderdunce” for marrying into the family. They just keep throwing mud, figuring some of it will stick. 😉