ABSTRACT
Objective:To investigate methods of molecular diagnosis and clinical features of 46, XY disorders of sexual development(DSD).Methods:A total of 206 cases of 46, XY DSD patients, who visited the Shanghai Ninth People′s Hospital, Shanghai Jiaotong University School of Medicine, from July 2009 to June 2021, underwent AA chip based on multiplex PCR and probe-capture-targeted next-generation sequencing. Clinical features of patients with genetic diagnosis were analyzed.Results:Among 206 patients, the diagnostic rate of patients with micropenis, hypospadias and cryptorchidism was the highest, up to 75.28%. Almost all patients had different degrees of undermasculinized external genitalia. The most frequent phenotype was micropenis with hypospadias(87.25%). Only one gene variant was detected in 81 patients(39.32%), multiple genetic variants were detected in 104 patients(50.49%), and no gene variant was identified in 21 patients(10.19%). 107 patients had definite genetic diagnosis, with a diagnostic rate of 51.94% by adding the pathogenic and likely pathogenic ratios following the American College of Medical Genetics and Genomics(ACMG) guidelines, including 40 patients of steroid 5α-reductase type 2(SRD5A2) variants(37.38%), 36 patients of androgen receptor(AR) variants(33.64%), 13 patients of steroidogenic factor 1(NR5A1) variants(16.82%), 6 patients of 17β-hydroxysteroid dehydrogenases 3(HSD17B3) variants(5.61%), 2 patients of 17α-hydroxylase/17, 20-lyase enzyme(CYP17A1), Wilms′ tumor 1(WT1) and GATA binding protein 4(GATA4) variants(1.87%), and one patient of luteinizing hormone receptor(LHCGR) variant(0.93%). Gynecomastia was found in 29 of 81 postpubertal patients, of which 25(86.21%) had AR variants.Conclusions:46, XY DSD presents complex clinical manifestations and molecular etiologies. Targeted nextgeneration sequencing has the advantages of high throughput, high efficiency and low cost, which has a high value especially in etiological diagnosis of 46, XY DSD with large genetic heterogeneity.