Comprehensive Clinical Overview of 48,XXYY Syndrome: Pathogenesis, Phenotype, Diagnosis, Management, and Prognosis
Epidemiology and Classification 48,XXYY syndrome is a rare sex chromosome aneuploidy affecting approximately 1 in 18,000–50,000 male births. It falls under the broader spectrum of Klinefelter variant syndromes, which includes 47,XXY (classic Klinefelter), 48,XXXY, and 49,XXXXY. Unlike classic Klinefelter (47,XXY), 48,XXYY involves two supernumerary sex chromosomes—one extra X and one extra Y—resulting in a 48,XXYY…
