title: Evidence that the human X chromosome is enriched for male-specific but not female-specific genes.
abstract: There is increasing evidence that X chromosomes have an unusual complement of genes, especially genes that have sex-specific expression. However, whereas in worm and fly the X chromosome has a dearth of male-specific genes, in mice genes that are uniquely expressed in spermatogonia are especially abundant on the X chromosome. Is this latter enrichment true for nongermline, male-specific genes in mammals, and is it found also for female-specific genes? Here, using SAGE data, we show (1) that tissue-specific genes tend to be more abundant on the human X chromosome, (2) that, controlling for this effect, genes expressed exclusively in prostate are enriched on the human X chromosome, and (3) that genes expressed exclusively in mammary gland and ovary are not so enriched. This we propose is consistent with Rice's model of the evolution of sexually antagonistic alleles.
authors.affiliation: Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Lercher
authors.forename: Araxi O
authors.initials: AO
authors.lastname: Urrutia
authors.forename: Laurence D
authors.initials: LD
authors.lastname: Hurst
mesh_terms: D000818:Animals; D005075:Biological Evolution; D004331:Drosophila melanogaster / Q000235:genetics; D005260:Female; D015870:Gene Expression; D008040:Genetic Linkage / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics*; D006801:Humans; D008297:Male; D042361:Mammary Glands, Human / Q000502:physiology; D051379:Mice; D010053:Ovary / Q000502:physiology; D011110:Polymorphism, Genetic / Q000235:genetics; D011467:Prostate / Q000502:physiology; D012098:Reproduction / Q000235:genetics; D012727:Sex Characteristics; D013093:Spermatogonia / Q000502:physiology; D014960:X Chromosome / Q000235:genetics*