PUBLIC RELEASE DATE: <\/p>\n
9-Jan-2014 <\/p>\n
Contact: Melissa A. Wilson Sayres mwilsonsayres@berkeley.edu<\/a> Public Library of Science<\/p>\n Is the male Y chromosome at risk of being lost? Recent work by Dr Wilson Sayres and colleagues at UC Berkeley, published in PLOS Genetics, demonstrates that the genes on the Y chromosome are important: they have probably been maintained by selection. This implies that despite its dwindling size, the Y chromosome will be sticking around. <\/p>\n The human Y chromosome contains 27 unique genes, compared to thousands on other chromosomes. Some mammals have already lost their Y chromosome (despite still having males, females and normal reproduction); this has led some researchers to speculate that the Y chromosome is superfluous. <\/p>\n As the X and Y chromosomes evolved, male-specific genes became fixed on the Y chromosome. Some of these genes were detrimental to females, so the X and Y chromosomes stopped swapping genes. This meant the Y chromosome was no longer able to correct mistakes efficiently and has thus degraded over time. <\/p>\n There is low genetic diversity in the human Y chromosome, and Dr Wilson Sayres and colleagues were able to precisely measure this by comparing variation on a person's Y chromosome with variation on that person's other 22 chromosomes, the X chromosome and the mitochondrial DNA. The researchers then showed that this low genetic diversity cannot be explained solely by a reduction in the number of males passing on their Y chromosome (successfully fathering male offspring). Instead, the low diversity must also result from natural selection, in this case purifying selection (the selective removal of deleterious alleles). <\/p>\n The movements of human populations around the world are tracked by variations in the Y chromosome. The increased understanding provided by this research will improve estimates of humans' evolutionary history. <\/p>\n ### <\/p>\n<\/p>\n <\/p>\n The rest is here:<\/p>\n The human Y chromosome is not likely to disappear<\/a><\/p>\n","protected":false},"excerpt":{"rendered":" PUBLIC RELEASE DATE: 9-Jan-2014 Contact: Melissa A. Wilson Sayres mwilsonsayres@berkeley.edu<\/a> Public Library of Science Is the male Y chromosome at risk of being lost? Continue reading