The proximate factors causing sex differences in physiology and disease are primary acute activational effects of gonadal hormones, organizational long-lasting effects of gonadal hormones, and sex chromosome effects not mediated by gonadal hormones. The X chromosome is a hot spot for sexually antagonistic fitness variation.
First, it could be the consequence of a heteropopulation lacking the appropriate suppressor for segregation distorters. When a specific cytosine is found to be methylated a few percent more often in one sex than the other, it is not clear how large a functional impact would be expected on gene function.
However, increased sexual selection and conflict can also affect Y chromosome evolution.
In many cases, these differences are caused by the long-lasting or permanent organizational effects of gonadal hormones Arnold and Gorski, Intralocus sexual conflict resolved through gene duplication. The likelihood that a sex-determining gene will be proximate to a locus with sexually antagonistic alleles is in many ways defined by the proportion of loci in the genome with sexually antagonistic effects.
Sex differences in the mammalian transcriptome.
Article Media. Full Name Comment goes here. At meiosis the X and Y chromosomes first pair then disjoin and pass to different cells. Perform a cross using a punnett square. Several traits, including red-green colour blindnessarise from the interaction of genes that are located on the X chromosome.
Visibility Others can see my Clipboard. No Downloads. The male of many animals has one chromosome pair, the sex chromosomes, consisting of unequal members called X and Y.
In other studies, however, Sry is proposed as a regulator of hypertension because of its effects on the renin-angiotensin system and sympathetic nervous system Turner et al. Nature : —U9. Sex chromosome-specific regulation in the Drosophila male germline but little evidence for chromosomal dosage compensation or meiotic inactivation.
Drosophila dosage compensation: A complex voyage to the X chromosome. Sex-linked expression of a sexually selected trait in the stalk-eyed fly, Cyrtodiopsis dalmanni. Sex and conflict.