| trisomy 21 syndrome | <syndrome> A common chromosome disorder due to an extra chromosome number 21 (trisomy 21). The syndrome causes mental retardation, a characteristic face, and multiple malformations. It is associated with a major risk for heart problems, a lesser risk of duodenal atresia (part of the intestines not developed), and a minor but still significant risk of acute leukaemia. Trisome 21 syndr0ome is also commonly called down syndrome after the 19th century english doctor langdon down who was curiously enough not the first person to describe the condition, added little to knowledge and, in great error, attributed the condition to a reversion to the mongoloid race. The disorder was also once called mongolism, a term now considered slang. (12 Dec 1998) |
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| trisomy 8 syndrome | <syndrome> Craniofacial dysmorphia, short wide neck but narrow cylindrical trunk, and multiple joint and digital defects. (05 Mar 2000) |
| trisomy C syndrome | <syndrome> Trisomy for any chromosome of group C, numbers 6 through 12, most often number 8. (05 Mar 2000) |
| trisomy D syndrome | <syndrome> A condition with three rather than the normal two chromosomes 13. Children born with this syndrome have multiple malformations and mental retardation due to the extra chromosome 13. The congenital malformations (birth defects) commonly include scalp defects, haemangiomas (blood vessel malformations) of the face and nape of the neck, cleft lip and palate, malformations of the heart and abdominal organs, and flexed fingers with extra digits. The mental retardation is profound. The iq is untestably low. The majority of trisomy 13 babies die soon after birth or in infancy. The condition is also called patau syndrome after the late geneticist klaus patau (at the university of wisconsin) who discovered the extra chromosome in 1960. (17 Dec 1998) |