Klinefelter syndrome, variants: A genetic condition where males have at least one extra X chromosome or extra copies of both the X and Y chromosomes in each cell. Normally male cells contain one X and one Y chromosome in each cell. The condition is not inherited but is a result of problems during cell division.
The list of signs and symptoms mentioned in various sources for Klinefelter syndrome, variants includes the 26 symptoms listed below: * Abnormal sexual development * Reduced intelligence * Distinctive facial features * Skeletal abnormalities * Poor coordination * Severe speech problems * Breast development in males * Reduced facial hair * Reduced body hair * Infertility * Underdevelopment of secondary sexual characteristics * Sparse body hair after puberty * Male breast enlargement * Azoospermia * Tall stature * Long legs * Overweight * Female pattern of fat distribution * Behavioral problems * Shyness * Poor judgment * Psychosocial maladjustment * Small penis * Small testes * Elbow dysplasia * Fifth finger clinodactyly Note that Klinefelter syndrome, variants symptoms usually refers to various symptoms known to a patient, but the phrase Klinefelter syndrome, variants signs may refer to those signs only noticable by a doctor.
Klinefelter's syndrome, probably the most common cause of hypogonadism, appears in approximately 1 in every 500 males. This disorder usually results from one extra X chromosome, giving such patients a 47,XXY complement instead of the normal 46,XY. (See Fertilization in Klinefelter's syndrome, page 36.) In the rare mosaic form of this syndrome, some cells contain the extra X chromosomes, whereas others contain the normal XY complement. The extra chromosome responsible for Klinefelter's syndrome probably results from either meiotic nondisjunction during parental gametogenesis or from meiotic nondisjunction in the zygote. The incidence of meiotic nondisjunction increases with maternal age.
The signs and symptom information on this page attempts to provide a list of some possible signs and symptoms of Klinefelter syndrome, variants. This medical information about signs and symptoms for Klinefelter syndrome, variants has been gathered from various sources, may not be fully accurate, and may not be the full list of Klinefelter syndrome, variants signs or Klinefelter syndrome, variants symptoms. Furthermore, signs and symptoms of Klinefelter syndrome, variants may vary on an individual basis for each patient. Only your doctor can provide adequate diagnosis of any signs or symptoms and whether they are indeed Klinefelter syndrome, variants symptoms.