XYY syndrome

XYY syndrome, also known as Jacobs syndrome, is an genetic disorder. People with this disorder have the wrong number of chromosomes in each of their cells, which is called aneuploidy. They have one X chromosome and 2 Y chromosomes in each cell. People with XYY syndrome are male, but normal males have one X chromosome and one Y chromosome.

• Nielsen, Johannes (1998). XYY males. An orientation.

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