SRY-negative 45,X/46,XY adult male with complete masculinization and infertility: A case report and review of literature

BACKGROUND: 45,X/46,XY mosaicism is a rare chromosomal abnormality with a wide range of phenotypes in both males and females, from normal individuals with different degrees of genital ambiguity to those who show signs of Turner’s syndrome. More rarely, cases of 45,X/46,XY mosaicism with a normal-appearing male phenotype are not found until a chromosome test is performed to investigate the cause of male infertility. CASE SUMMARY: In this study, a 29-year-old male patient with complete azoospermia is reported. Chromosomal analyses of his lymphocytes revealed the karyotype 45,X[93%]/46,X,+mar(Y)[7%]. In addition, Y chromosome-specific markers, such as SRY, ZFY, AZFa, AZFb and AZFc, were not observed in his blood DNA according to multiplex polymerase chain reaction test. A literature review identified several 45,X/46,XY cases with a normal-appearing male phenotype, most of whom were diagnosed during infertility investigation. However, the present case is the first SRY-negative 45,X/46,XY male case diagnosed during a premarital medical examination. CONCLUSION: This finding further suggests that sex determination is a complex process regulated by multiple genetic and environmental factors.