【摘要】 本文对100例Down综合征患儿的外周血细胞进行了核型分析。结果发现21三体型、易位型和嵌合型依次为91％、2％和7％。21三体型患儿出生时父亲的平均年龄为36.6岁,母亲的平均年龄为33.5岁。全部患儿智能低下,呈典型的先天愚型面容和体征。2例易位型均为Robertson式易位(14q;21q),其中1例的父母的核型正常,但其姊为Turner综合征患者(45,XO)。另1例的父亲为平衡易位携带者(14q;21q)。对嵌合型定期进行了核型随访,发现在患儿1岁左右正常细胞与21三体细胞嵌合的比例呈动态变化,而在2岁以后则渐趋稳定。更多还原

【Abstract】 The kayotype of the peripheral blood cells in 100 cases of Down syndrome was analyzed. It was found that 21 trisomy, translocation and mosaic comprised 91%, 2% and 7% respectively. The average age of the fathers of the patients with 21 trisomy was 36.5 years and that of the mothers was 33.5. All the children were mentally retarded and characterized by the typical features and signs of Down syndrome. Two cases of translocation were of Robertsonian type (14q; 21q). The karyotype of the parents was normal in one case, while his sister was affected with Turner syndrome (45, XO). The father of the other case was a balanced carrier (14q; 21q). The karyotype of the mosaics was followed up regularly and found that there was a kinetic change of the proportion of the normal cells and 21 trisomic cells within the first year of life, and it tended to be stable after 2 years of age.更多还原