Which chromosomal abnormality occurs when a male has an extra X chromosome?

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Multiple Choice

Which chromosomal abnormality occurs when a male has an extra X chromosome?

Explanation:
Having an extra X chromosome in a male is a sex chromosome aneuploidy known as Klinefelter syndrome. Typically males have 46,XY, but when an extra X is present, the karyotype becomes 47,XXY. The additional X disrupts normal testicular development and lowers testosterone levels, which can lead to features such as reduced fertility, smaller testes, and sometimes taller stature or other secondary sex characteristic differences. The key idea is that the presence of an extra X in a male’s chromosomes defines this specific syndrome. Turner syndrome, by contrast, involves only one X chromosome (45,X) and occurs in individuals with a typically female phenotype. Triple X syndrome involves an extra X in females (47,XXX). Androgen insensitivity syndrome occurs in some 46,XY individuals where the body’s cells don’t respond properly to androgens, producing a typically female or ambiguous external phenotype without an extra X chromosome.

Having an extra X chromosome in a male is a sex chromosome aneuploidy known as Klinefelter syndrome. Typically males have 46,XY, but when an extra X is present, the karyotype becomes 47,XXY. The additional X disrupts normal testicular development and lowers testosterone levels, which can lead to features such as reduced fertility, smaller testes, and sometimes taller stature or other secondary sex characteristic differences. The key idea is that the presence of an extra X in a male’s chromosomes defines this specific syndrome.

Turner syndrome, by contrast, involves only one X chromosome (45,X) and occurs in individuals with a typically female phenotype. Triple X syndrome involves an extra X in females (47,XXX). Androgen insensitivity syndrome occurs in some 46,XY individuals where the body’s cells don’t respond properly to androgens, producing a typically female or ambiguous external phenotype without an extra X chromosome.

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