Gene expression, chromosome heterogeneity and the fast-X effect in mammals.
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ABSTRACT:
SUBMITTER: Nguyen LP
PROVIDER: S-EPMC4360113 | biostudies-literature | 2015 Feb
REPOSITORIES: biostudies-literature
Publications
Gene expression, chromosome heterogeneity and the fast-X effect in mammals.
Nguyen Linh-Phuong LP Galtier Nicolas N Nabholz Benoit B
Biology letters 20150201 2
The higher rate of non-synonymous over synonymous substitutions (dN/dS) of the X chromosome compared with autosomes is often interpreted as a consequence of X hemizygosity. However, other factors, such as gene expression, are also known to vary between X and autosomes. Analysing 4800 orthologues in six mammals, we found that gene expression levels, associated with GC content, fully account for the variation in dN/dS between X and autosomes with no detectable effect of hemizygosity. We also repor ...[more]
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