XXXY syndrome - Wikipedia
https://en.wikipedia.org/wiki/XXXY_syndrome 
Overview
Signs and symptoms
Cause
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XXXY syndrome is a genetic condition characterized by a sex chromosome aneuploidy, where males have two extra X chromosomes. Males typically have only two sex chromosomes, an X and a Y. The presence of one Y chromosome with a functioning SRY gene causes the expression of genes that determine maleness. Because of this, XXXY syndrome only affects males. The additional two X chromosomes in males with XXXY syndrome causes them to have 48 chromosomes, instead of the typ…
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Other names: 48,XXXY syndrome