The Y chromosome is not going away


Accessible research: Natural selection reduced diversity on human Y chromosomes
[Via The Panda’s Thumb]

We just had a paper published over at PLoS Genetics entitled, “Natural selection reduced diversity on human Y chromosomes.” But, as you may recall, it has been available on the arXiv for quite some time.

Others have already summarized the work (Razib Khan nails the punchline, and Ian Sample has a summary for the popular press).

Below are answers to many of the questions I received about this work.

How would you describe the importance of your findings?

Human chromosomes by Paquete

The human sex chromosomes, X and Y, used to be nearly identical, but now the Y has lost 90% of the genes it once shared with the Y, and some have speculated that the Y chromosome will disappear in less than five million years. We show that human Y chromosomes are much more similar to each other than expected. Previously, variance in male reproductive success (meaning some men fathering many children, and some men fathering few or none), was thought to explain this similarity, but we show that an additional force, natural selection, is needed to reduce diversity across Y chromosomes to the levels we observe. 


What is critical here is that the important parts of the Y chromosome that appear to be most important have been mostly ignored. Because they are such trouble to examine.

So maybe people will do that examination. That is a problem with DNA sequencing now. We can do the easy stuff really easily and cheaply. But it is that last little bit, which may hold real importantce that often gets lost in the shuffle.