Meiotic Origins of Non-Mosaic Klinefelter Syndrome (47, XXY): Mechanisms, Dimorphism, and Emerging Genetic Susceptibility.
BACKGROUND Non-mosaic Klinefelter syndrome (47,XXY) arises from sex-specific meiotic mechanisms leading to nondisjunction during gametogenesis. In maternal cases, errors occur predominantly during meiosis I, frequently involving X chromosomes that lack crossovers or exhibit crossovers outside optimal chromosomal locati...