Grace H J, Evetts D, Friedlander F C, Boughton K
S Afr Med J. 1980 Jul 19;58(3):117-9.
A young unrelated Indian couple produced a baby who had an unusual facies, marked abdominal distension and muscular hypotonia. At 8 weeks cytogenetic investigation revealed what appeared to be trisomy-21. Because this did not agree with the clinical signs the parents were tested and the mother was found to have a balanced translocation between chromosomes 12 and 14; her karyotype was 46,XX,rcp(12; 14)(p11; q11) and it was realized that her son had inherited her translocation chromosome involving the short arms of chromosomes 12 and 14. He thus had trisomy-12p. The present case and 10 others reported in the literature confirm that trisomy-12p produces a recognizable syndrome. Parents carrying a balanced translocation have a 50:50 risk of producing an abnormal infant at every pregnancy because both the trisomic and monosomic conditions may be viable. Amniocentesis for fetal karyotyping must be recommended to the couples concerned.
一对年轻的非亲属印度夫妇生下了一个婴儿，该婴儿面部异常、腹部明显肿胀且肌张力低下。8周时，细胞遗传学检查显示似乎是21三体综合征。但这与临床症状不符，于是对父母进行了检测，发现母亲的12号和14号染色体之间存在平衡易位；她的核型为46,XX,rcp(12; 14)(p11; q11)，并且发现她的儿子遗传了她涉及12号和14号染色体短臂的易位染色体。因此，他患有12号染色体短臂三体综合征。本病例以及文献中报道的其他10例病例证实，12号染色体短臂三体综合征会产生一种可识别的综合征。携带平衡易位的父母每次怀孕生出异常婴儿的风险为50:50，因为三体和单体情况都可能存活。必须向相关夫妇推荐进行羊膜穿刺术以进行胎儿核型分析。
