Autosome transposition events from Y chromosome among mammalsWHITEHEAD INSTITUTE, JENNIFER HUGHESThe mammalian Y chromosome has lost many hundreds of genes throughout evolution. Surviving Y chromosome genes were recently shown to have broadly important cellular functions, rather than male-specific roles, plus corresponding copies on the X chromosome. Following on a large survey of the evolution of the mammalian Y chromosome published last year, Jennifer Hughes, a research scientist in David Page’s laboratory at the Whitehead Institute in Cambridge, Massachusetts, and her colleagues now provide evidence to suggest that four presumably essential and highly conserved genes lost from the Y chromosome in several mammalian species—including humans—have been preserved in the genome through transposition onto autosomal chromosomes. The team’s results were published today (May 28) in Genome Biology.
This preservation of essential Y chromosome genes through transposition was previously thought to have occurred only in isolated cases, such as the loss of the entire Y chromosome in the Ryukyu spiny rat. The new work suggests that migration of important genes from a sex chromosome to an autosome is more prevalent in mammals than expected.
“This is an interesting story. It’s remarkable to see how consistently genes that were lost from the Y chromosome were rescued by autosomal copies in multiple species,” said Christine Disteche, who studies the regulation of mammalian sex chromosomes at the University of Washington and was not involved in the current work. “What is amazing is that this seemed to have happened independently in multiple lineages. That stresses how important ...