一例46，XY女性患者SRY基因的无义突变分析

A NONSENSE MUTATION IN THE HMG BOX OF THE SRY GENE IN A PATIENT WITH 46,XY SEX REVERSAL

采用ＰＣＲ－ＳＳＣＰ检测及ＤＮＡ测序技术，对一例４６，ＸＹ女性患者ＳＲＹ基因的ＨＭＧ基序进行了突变分析。结果发现在该基因的Ｓｐ引物扩增区域内存在突变。进一步的ＤＮＡ序列分析证实该突变为第６９９位碱基Ｃ被Ｔ置换，导致产生终止密码子的无义突变。结合临床表型可以认为本例患者的性反转是由于该突变所致。这一研究结果为ＳＲＹ基因是ＴＤＦ最佳候选基因的假说提供了一直接证据，有助于进一步阐明４６，ＸＹ女性发病的分子机理和ＳＲＹ基因在性别决定中的作用。

The HMG region in SRY gene of a patient with 46,XY karyotype and gonadal dysgenesis was analyzed using the PCR-SSCP and DNA sequencing techniques.The result revealed a point mutation at position 699 in SRY gene which changes the codon for leu to a stop codon. Therefore,it is suggested that the female phenotype and the gonadal dysgenesis of the patient is resulted from the nonsense mutation.This finding also supports the hypothesis that SRY plays an important role in normal male sex differentiation.