Down's syndrome is the most common cause of mental retardation (see mental retardation entry) and malformation in newborns. It occurs because of the presence of an extra chromosome. Chromosomes are structures that carry genetic information in...

Down Syndrome Also referred to as Down toll-free (800) 232-NDSC National Down Syndrome Society Address: 141 Fifth Avenue, Suite 75 New York, NY 10010 Telephone: (212)...

Down syndrome, also called trisomy 21, is the single most common genetic cause of moderate mental retardation. It occurs in about one of every eight hundred live births. It is caused by the inheritance of an extra copy of chromosome 21. The condition...

Down syndrome, also known as trisomy 21, is the most common identifiable form of mental retardation caused caused by an extra copy of chromosome 21 in the patient's set of chromosomes (karyotype). Nevertheless, this condition is also associated with...

A chromosomal abnormality that is the commonest cause of MENTAL HANDICAP in children, affecting 1 in 600 live births. Once known as mongolism, Down syndrome is characterized by distinctive morphological features in the development of the face and neck,...

Records about the existence of Down's syndrome date back to the Saxons, from whom we have anecdotal reports of the disorder. The first medical report of the condition was not published, however, until 1866. In that year, the British physician, J....

Records about the existence of Down's syndrome date back to the Saxons, from whom we have anecdotal reports of the disorder. The first medical report of the condition was not published, however, until 1866. In that year, the British physician, J....

Records about the existence of Down's syndrome date back to the Saxons, from whom we have anecdotal reports of the disorder. The first medical report of the condition was not published, however, until 1866. In that year, the British physician, J....

former (until 1973) county, eastern Northern Ireland. It was bounded by Belfast Lough (inlet of the sea; north), the Irish Sea (east), Carlingford Lough (south), former County Armagh (west), and former County Antrim (northwest). Down had an area of 952...

Congenital disorder caused by an extra chromosome (trisomy) on the chromosome 21 pair. Those with the syndrome may have broad, flat faces; up-slanted eyes, sometimes with epicanthal folds (whence its former name, mongolism); intellectual disability...

Trisomy 21 refers to the acquisition of an extra copy (there are three not two—hence trisomy) of chromosome 21 at MEIOSIS (see CELL DIVISION;). The most common condition this leads to is DOWN SYNDROME, though there is also evidence for trisomy 21...

Down syndrome or trisomy 21 (usually Down's Syndrome in British English[1]) is a genetic disorder caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British doctor who described it in 1866. The...