Natural Selection Reduced Diversity on Human Y Chromosomes
Research output: Contribution to journal › Journal article › Research › peer-review
Documents
- Natural Selection Reduced Diversity on Human Y Chromosomes
Final published version, 359 KB, PDF document
The human Y chromosome exhibits surprisingly low levels of genetic diversity. This could result from neutral processes if the effective population size of males is reduced relative to females due to a higher variance in the number of offspring from males than from females. Alternatively, selection acting on new mutations, and affecting linked neutral sites, could reduce variability on the Y chromosome. Here, using genome-wide analyses of X, Y, autosomal and mitochondrial DNA, in combination with extensive population genetic simulations, we show that low observed Y chromosome variability is not consistent with a purely neutral model. Instead, we show that models of purifying selection are consistent with observed Y diversity. Further, the number of sites estimated to be under purifying selection greatly exceeds the number of Y-linked coding sites, suggesting the importance of the highly repetitive ampliconic regions. While we show that purifying selection removing deleterious mutations can explain the low diversity on the Y chromosome, we cannot exclude the possibility that positive selection acting on beneficial mutations could have also reduced diversity in linked neutral regions, and may have contributed to lowering human Y chromosome diversity. Because the functional significance of the ampliconic regions is poorly understood, our findings should motivate future research in this area.
Original language | English |
---|---|
Article number | e1004064 |
Journal | PLOS Genetics |
Volume | 10 |
Issue number | 1 |
Number of pages | 12 |
ISSN | 1553-7390 |
DOIs | |
Publication status | Published - 2014 |
Externally published | Yes |
Number of downloads are based on statistics from Google Scholar and www.ku.dk
ID: 222644097