An Infant With DHX37 Variant: A Novel Etiology of 46,XY DSD and Literature Review

46,XY sex reversal 11 (SRXY11) is a rare and recently identified form of 46,XY difference in sexual development (DSD), caused by variants in the DEAH-Box Helicase 37 gene (DHX37). DHX37 is crucial for ribosome biogenesis, but its specific role in gonadal development remains unclear. The genital phenotype varies widely, ranging from typical female to typical male. We present a 46,XY infant with prenatal ultrasound findings of atypical genitalia. Amniotic fluid gene analysis revealed a known heterozygous pathogenic variant in DHX37, p.R308Q (c.923G>A), confirmed postnatally. The patient was born with markedly undervirilized genitalia with posteriorly fused labioscrotal folds, a single introitus, no clitoromegaly, and nonpalpable gonads. Laboratory evaluation at multiple points showed undetectable anti-Müllerian hormone (AMH) and inhibin B levels, elevated gonadotropin levels, and negligible testosterone levels. Clinical course was complicated by urine retention in the vagina and uterus and hydronephrosis requiring catheterization. Endoscopy revealed a urogenital sinus with separate urethral and vaginal openings and 2 cervices leading into 2 separate uteri suggestive of a bicornuate bicollis uterus. Laparoscopy revealed 2 intra-abdominal gonads adjacent to the fallopian tubes. Evidence for inheritance, penetrance, genotype-phenotype correlation, and risk of malignancy in SRXY11 is limited to case reports.