17α-羟化酶缺陷症临床及分子遗传学研究

Clinical and molecular genetic features of 17α-hydroxylase deficiency: study of a case

目的探讨发生在17α-羟化酶缺陷症患者的罕见股骨颈骨折的诊治方法。方法详细收集患者临床资料、进行全面的体检和辅助检查。采用激素替代治疗并对股骨颈骨折进行手术治疗。通过分子遗传学研究明确诊断并探究其基因基础。结果病史、体检和辅助检查支持17α-羟化酶缺陷症的诊断。对移位的股骨颈骨折在椎管内麻醉下施行闭合复位空心钉内固定术,恢复患肢功能。分子遗传学研究发现该患者为CYP17A1基因纯合突变,第6号外显子6436-6438(TAC→AA)导致Y329K,418X。导致形成缺乏酶活性中心的截短蛋白。结论发生在17α-羟化酶缺陷症患者的股骨颈骨折可以通过手术治疗恢复患肢功能。CYP17A1基因第6号外显子TAC329AA突变在我国有一定的种族特异性。

Objective To study the clinical and molecular genetic features of 17α-hydroxylase deficiency and treatment of femoral neck fracture complicated therein. Methods A patient with 17α- hydroxylase deficiency with femoral neck fracture, with social sex as female, aged 19, underwent thorough clinical assessment, including history collection, physical examination, and laboratory test. Hormonal replacement therapy was applied and closed replacement was performed on the fractured femoral neck. Molecular genetic method was adopted to explore the gene mutation. Results The patient was diagnosed as 17α-hydroxylase deficiency according to clinical assessment. Under spinal anesthesia, the displaced femoral neck was reduced closely and fixed using 3 cannulated screws. Ten-month follow-up showed that the function of the injured hip was recovered. Genetic examination showed homozygous mutation in the exon 6 ： 6436 - 6438（TAC→AA） , causing amino acid missence mutation Y329K and 418X. Conclusion Femoral neck fracture in 17α-hydroxylase deficiency patient can be treated successfully by operative method. 6436 -6438 （TAC→AA） mutation in CYP17A1 gene may be a prevalent mutation causing 17α-hydroxylase deficiency in China.