Klinefelter syndrome (KS) is the most common genetic form of male hypogonadism, but the phenotype becomes evident only after puberty. During childhood, and even during early puberty, pituitary-gonadal function in 47,XXY subjects is relatively normal, but from midpuberty onwards, FSH and LH levels increase to hypergonadotropic levels, inhibin B decreases to undetectable levels, and testosterone ...

Most multiple congenital abnormality syndromes associated with uveal colobomata have their origins dating from before intrauterine development. Causative genetic and chromosomal influences were reviewed (James, Karseras, and Wybar, 1974), but associated abnornalities of the sex chromosomes were not observed in their series and are a rare occurrence in the literature. It is of interest therefore...