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47,XYY Syndrome

By

Nina N. Powell-Hamilton

, MD, Sidney Kimmel Medical College at Thomas Jefferson University

Reviewed/Revised Oct 2023
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47,XYY syndrome is the presence of two Y chromosomes and one X chromosome in a phenotypic male.

The 47,XYY syndrome occurs in approximately 1/1000 live male births.

XYY syndrome was once thought to cause aggressive or violent criminal behavior, but this theory has been disproved.

View PATIENT EDUCATION
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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