应用MLPA技术进行3例猫叫综合征的分子遗传学分析

目的通过应用多重连接依赖式探针扩增（MLPA）技术对3例猫叫综合征（CDCS，5p缺失综合征）进行分析，旨在探索可快速诊断CDCS的分子遗传学方法。方法对3个CDCS患者及其父母、患者1的异卵双生之姐姐，进行MLPA分析，检测CDCS关键区域5p15．33：包括hTERT基因在内的9个位点的基因拷贝数的变化；同时，对相应标本进行染色体G-显带核型分析。结果在接到标本24—48h，MLPA示：3例患儿均存在CDCS关键区域5p15．33包含hTERT在内的基因缺失，其父母及患者1异卵双生之姐姐未见缺失。7—10天后G显带染色体核型分析示：患儿2、3为单纯5号短臂（5p）末端缺失，其父母正常；患儿1病例在国内尚属少见，核型为：45，XY，-22，-5p，4-der（5）t（5；22），携带了一条源于5p和22p易位而来衍生的5号染色体，其父母及异卵双生之姐姐均正常。MLPA与核型分析结果-致：3例患儿均为CDCS患者。结论MLPA是-种可快速诊断CDCS的分子遗传学方法，具有临床应用价值。

Application multiplex ligation - dependent probe amplificationto detect 3 cases of Cri - du - Chat syndrome.

Objective ： By using multiplex ligation - dependent probe amplification （MLPA） aimed at explore a rapid dignosis methods to Cri - du - Chat syndrome （ CDCS or 5p deletion syndrome）, with molecular genetics techniques. Methods ： For the 3 cases and their parents and fraternal twins sister of case 1, MLPA were used to detect copy number changes of gene at the critical region 5 plS. 33 of CDCS, where including hTERT gene. Chromosome G -banding karyotype analysis as well as were performed on the corre-sponding samples at the same time. Results ： It was shown with MLPA in 24 - 48 hours ： there had copy number deletion of the hTERT gene at the critical region 5 plS. 33 of CDCS of 3 case. All of them are CDCS while their parents and fraternal twins sister of case 1 showed a normal karyotype pattern. After 7 - 10 days, G - banded karyotype analysis of Cases 2 and 3 revealed abnormal 46, XX, del （5） （p13 - 15） female karyotypes, and their parents showed a normal karyotype pattern; But for case 1, which showed an abnormal karyotype involving a balanced translocation 45, XY, - 22, - 5 p, ＋ der （5） t （5 ; 22）, and there are derivative chromosome 5 carry out a 5 p and 22 p translocation, and their parents and fraternal twins sister of case 1 showed a normal karyotype pattern. The karyotypes results shown that 3 cases were CDC, which were in accordance with MLPA. Conclusion： MLPA could be as a rapid molecular genetic techniques to diagnose CDCS, and which have clinical application value.