X chromosome

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The X chromosome is one of the sex chromosomes of mammals (the other being the Y chromosome). Females have two X chromosomes, whilst males have one X and one Y chromosome. In the somatic cells of females one X is inactivated by the formation of a Barr Body.

X chromosome is a sex chromosome in human being. There are totally two sex chromosome in human, the other sex chromosome is Y chromosome. Each persone have one pair of sex chromosome in each cells. There are two X chromosome in the Female and One X chromosome and one Y chromosome in the male.

The X Chromosome contains a number of genes, therefore a number of genetic traits/diseases/defects can affect Males (with only one X allele) and Females (who have 2 copies) This is because in women, only if both copies of an allele are recessive, the phenotype will be recessive - yet if only one of the alleles is already dominant, then the recessive allele is disregarded. However, in men there is no other such allele (due to them not having two, but one X chromosome). As such, whatever genotype men have in the X chromosome will always be expressed.. The phenotypic expression of a gene on an X or Y chromosome is known as Sex Linkage

Some individuals with Aneuploidy possess an odd number of X chromosomes, in such diseases like Klinefelter syndrome (XXY) and Turner syndrome (XO)

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