XYY Syndrome

XYY Syndrome or 47,XYY or Jacob's Syndrome is an intersex trait affecting approximately 1/1000 AMAB individuals, and causes them to have extra Y chromosomes, typically only one.

Resources

 * 1) https://ghr.nlm.nih.gov/condition/47xyy-syndrome
 * 2) https://rarediseases.org/rare-diseases/xyy-syndrome/
 * 3) https://www.deviantart.com/pride-flags/art/XYY-Syndrome-658903420