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通过ＤＮＡ序列测定在一名４６，ＸＹ女性性反转患者ＳＲＹ基因启动子区发现了一个新的突变：ｎｔ．－８１Ｇ→Ａ．该突变不见于正常男性，因此不是ＤＮＡ多态性．为了检测这一点突变对ＳＲＹ基因表达功能的影响，构建了分别由正常或突变的人ＳＲＹ基因启动子区片段调控氯霉素乙酰转移酶（ＣＡＴ）报告基因表达的两个质粒，寡核苷酸探针杂交证实该启动子片段正常或携带有Ｇ→Ａ突变．这两个质粒分别与ｐＳＶ－β－半乳糖苷酶内对照质粒共转染ＨｅＬａ细胞后，瞬间表达分析显示这一突变对ＣＡＴ酶活性水平无显著影响（０．５０＞Ｐ＞０．２０）．上述正常和突变的ＳＲＹ基因启动子片段与Ｋ５６２细胞核抽提物的凝胶阻滞实验也表明，突变对Ｋ５６２细胞核蛋白与ＳＲＹ基因启动子区的结合影响不大．研究ＳＲＹ基因的表达调控对阐明人的性别决定机制及性反转的病理机制具有重要意义
A novel mutation was found in the promoter region of the SRY gene in a 46-year, 46-year-old female with XY reversal by DNA sequencing: nt. -81G → A. This mutation is not seen in normal males and is therefore not DNA polymorphism. To examine the effect of this mutation on SRY gene expression, two plasmids were constructed that regulate the expression of the chloramphenicol acetyltransferase (CAT) reporter gene from normal or mutant human SRY promoter regions, respectively. Oligonucleotides Probes hybridization confirmed that the promoter fragment was normal or carrying a G → A mutation. After co-transfection of these two plasmids with control plasmids of pSV-β-galactosidase and HeLa cells, the transient expression analysis showed that this mutation had no significant effect on CAT activity (0.50> P> 0.20) . The gel retardation experiments of the normal and mutant SRY gene promoter fragments and K562 cell nuclear extracts also showed that the mutation had little effect on the binding of the K562 cell nucleoprotein to the SRY gene promoter region. It is important to study the regulation of SRY gene expression to clarify the mechanism of human sex determination and the pathological mechanism of sexual inversion