SRY基因检测对性分化异常诊断和分类的意义

The role of SR Y in diagnasis of patients with gonadal dysgenesis

对１６例性腺发育不全患者的外周血白细胞、皮肤和双侧性腺的基因组ＤＮＡ标本，采用多聚合酶链式反应检测ＳＲＹ基因保守序列，以期从分子水平揭示性分化异常的原因。１６例中雄激素不敏感综合征５例、１７ａ羟化酶缺乏症１例、真两性畸形４例、４５，Ｘ性腺发育不全１例、ＸＹ单纯腺发育不全１例、睾丸退化１例、血核型４６，ＸＹ但已娩正常儿１例以及ＸＯ／ＸＹ性腺发育不全２例。１６例性分化异常血ＳＲＹ阳性１５例，１３例性腺病理有睾丸与外周血ＳＲＹ相符，２例性腺为卵巢或卵巢间质；ＳＲＹ阴性１例性腺也有发育不全睾丸。４６，ＸＹ女性且生育的患者进行了外周血ＳＲＹ基因保守序列的测定，未发现突变位点。测定ＳＲＹ可预示有睾丸的存在。结果显示ＳＲＹ基因检测比外周血核型能更好地预示睾丸的存在；性腺的病理取决于性腺部位的染色体核型和ＳＲＹ基因；除ＳＲＹ基因外，可能存在有其它决定性别的基因。

bjective:To clarify the role of SRY in diagnosis of gonadal dysgenesis. Patients :Sixteen cases of gonadal dysgenesis :androgen insensitivity syndrome( 5 )17-hydroxylase defi-ciency 1, true herrnaphrodite(4), 45,X/46, XY gonadal dysgenesis (2). 45,X gonadal dysgenesis,XYpure gonadal drsgenesis,testicular regression (one each )and a case of XY female who gave birth to a normalbaby. Methods :Detection of SRY gene in blood ,skin and gonads using polyrmerase chain reaction(PCR )anddirect sequencing of SRY motif.Results: Among the 16 catses,15 were blood SRY positive,among whom 13 (87%)showed presenceof testicular tissue, but 2 showed ovaries without testicular tissue;and on the contrary 1 SRY negative caseshowed presence of testicular tissue.The karotype and SRY detection of gonads correlated with pathologicalfindings in 3 cases,but not with blood karotype. Sequencing of SRY motif in a XY female who gave birthto a normal baby, showed no mutation.Conclusions : SRY detectiorn was more sensitive and specific than blood karyotype in the prediction of thepresence of testicular tissue. Peripheral blood karyotype does not necessary reflect the type of the gonads. There migth be some testicular related factors other than SRY gene.