染色体4号长臂和9号短臂移位的遗传分析

目的 探讨母子4号和9号染色体移位的遗传效应。方法 无菌采集外周血，采用微量淋巴细胞培养法进行染色体制作，G显带分析染色体核型，并通过调查病史分析其遗传效应。结果 母亲染色体核型为46，XX，t（4；9）（q31；p24），其子染色体核型为46，XY，der（9）t（4；9）（q31；p24）mat。其子的异常9号染色体是由母亲遗传而来。结论 母亲为染色体平衡移位携带者，患儿的异常9号染色体为母源的，该母亲出生正常后代的几率仅为1／18，故加强婚前和产前染色体检查对预防染色体病儿出生意义重大。

Genetic analysis of translocation of chromosome t (4;9) in a child with rare chromosome abnormality

A 10-month-old boy suspected of genetic abnormality was admitted for fever and coughing. Routine G-banding chromosome analysis of the peripheral blood lymphocytes and hereditary pattern analysis on the basis of the karyotpes and disease history revealed that the karyotype of the boy's mother was 46, XX,t(4;9)(q31;p24), and that of the boy was XY,der(9)t(4;9)(q31;p24)mat. The mother was identified as a carrier of balanced translocation of the chromosome who gave the abnormal chromosome 9 to her son, and she had only a chance of 1:18 to have a normal offspring. This case reiterates the importance of antemarital examination and prenatal diagnosis for preventing chromosomal diseases.