49,XXXYY syndrome

49, XXXYY syndrome is a rare chromosomal condition that occurs when a male inherits two extra copies of the X chromosome and one extra copy of the Y chromosome. This syndrome has been described in only a few cases in the medical literature. People with this condition may have distinctive facial features, may be of normal to tall height, and sometimes experience additional physical and developmental challenges. Information about the condition is still limited due to its rarity.

Reported signs and symptoms in people with this syndrome include severe intellectual disability, distinctive facial features, normal to tall stature, gynecomastia (enlargement of breast tissue), hypogonadism (underactive testes), and behavioral abnormalities.

49, XXXYY syndrome is most likely caused by a mistake called nondisjunction, which occurs either at conception or during the formation of the sperm and/or egg. This error in the number of chromosomes results in the extra copies of X and Y chromosomes seen in this condition.

Treatment for 49, XXXYY syndrome is based on the specific signs and symptoms present in each person. Medical care is tailored to address the individual challenges faced by people with this condition.

Information about prognosis is currently limited for this condition.

Information about current research and future directions is currently limited for this condition.