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13.2: Sex Chromosomes and Sex Determination

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    75226
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    • 13.2.1: Sex Chromosomes
      The nuclei of human cells contain 22 autosomes and 2 sex chromosomes. In females, the sex chromosomes are the 2 X chromosomes. Males have one X chromosome and one Y chromosome. The presence of the Y chromosome is decisive for unleashing the developmental program that leads to a baby boy.
    • 13.2.2: Inferring the Mode of Inheritance
      Given a pedigree of an uncharacterized disease or trait, one of the first tasks is to determine which modes of inheritance are possible and then which mode of inheritance is most likely. This information is essential in calculating the probability that the trait will be inherited in any future offspring. We will mostly consider five major types of inheritance: autosomal dominant (AD), autosomal recessive (AR), X-linked dominant (XD), X-linked recessive (XR), and Y-linked (Y).


    13.2: Sex Chromosomes and Sex Determination is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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