XXYY or 48,XXYY syndrome or 48,XXYY is a rare intersex trait occurring in approximately 1 in 18,000 or 1 out of 40,000 people who are assigned male at birth, and causes them to have an extra X and an extra Y chromosome.
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XXYY or 48,XXYY syndrome or 48,XXYY is a rare intersex trait occurring in approximately 1 in 18,000 or 1 out of 40,000 people who are assigned male at birth, and causes them to have an extra X and an extra Y chromosome.