Cytogenetic and molecular detection of a rare unbalanced Y;3 translocation in an infertile male: A case report

INTRODUCTION: The infertile male individuals carrying the Y-autosome translocations are seldom reported in clinic. Herein, we described a severe oligozoospermic male with rare unbalanced Y;3 translocation transmitted through 3 generations. PATIENT CONCERNS: A 33-year-old Chinese male was referred for infertility consultation in our center after 10 years’ primary infertility. He was diagnosed as severe oligozoospermia according to the semen analysis. DIAGNOSIS: G-banding analysis initially described the karyotype as 46, XY, add (3) (p26) for the patient, and his wife's karyotype was 46, XX. The chromosomal microarray analysis identified 3.81Mb and 0.29Mb duplications in Yq11.223q11.23 and Yq12, separately. No deletions were detected in azoospermia factors (AZF)a, AZFb and AZFc. Fluorescence in situ hybridization analysis further confirmed the existence of sex-determining region Y gene and verified that Yq12 was translocated to the terminal short arm of chromosome 3(3p26). INTERVENTIONS: The couple chose intracytoplasmic sperm injection to get their offspring. The wife underwent amniocentesis for cytogenetic analysis but suffered termination of pregnancy due to premature rupture of membranes. OUTCOMES: The karyotype of the patient was finally described as 46, X, der(3)t(Y;3)(q11.22;p26). His father and the aborted fetus showed the same karyotypes as the patient. CONCLUSION: Our study not only enriched the karyotype-phenotype correlation of Y-autosome translocation, but also strengthened the critical roles of molecular genetic techniques in identifying the chromosomal breakpoints and regions involved.