21三体综合征是常染色体异常遗传性疾病中最常见的一种,它的主要临床特征为严重智力障碍。我院在遗传咨询门诊中发现一例罗伯逊易位引起14/21不平衡易位21三体综合征的患儿,经追溯连续三代发现5例14/21染色体罗伯逊易位,现将其家系及其染色体检查结果 Trigeminal syndrome is the most common form of autosomal abnormality and its main clinical feature is severe mental retardation. In our hospital, we found a case of Robertson’s translocation in the genetic counseling clinic which caused 14/21 unbalanced translocation in 21 trisomy. Five cases of Robinzook’s translocation on chromosome 14/21 were found retrospectively for three consecutive generations. Chromosome test results