To explore the significance of multiple genetic detection techniques in the differential diagnosis of chromosome karyotype in a child with hypospadias.

The case information of a child with hypospadias from the Urinary Surgery of Women and Children′s Medical Center Affiliated to Guangzhou Medical University was collected. The peripheral bloods of the child and his parents were extracted, and chromosome karyotype analysis, multicolorfluorescence in situ hybridization (M-FISH) technique, chromosome microarray analysis (CMA) and sex-determining region on the Y chromosome (SRY) were used for genetic analysis to determine the chromosomal karyotypes and sex of the children.

The child was male, 6 months old, the second fetus. The mother was preterm at 32 weeks due to pregnancy hypertension syndrome. The birth height was 48 cm, the weight was 2.3 kg, and the urine was found to be discharged from the ventral side of the penis during urination immediately after birth, without frequent urination or painful urination. Physical examination showed poor penis development, cap shaped accumulation of foreskin, urethral meatus at the root of the penis body, no local inflammation, and bilateral gonad being touched in scrotum. The ultrasound of scrotum showed no obvious abnormality in both testis and epididymis. The karyotype of the baby′mother was normal. The karyotype of his father was 45, X, ? psu dic(Y; 15) (q11.23; p13), so the karyotype of the baby was preliminarily diagnosed with 45, X, ? psu dic(Y; 15)(q11.23; p13)pat. CMA and SRY indicated that the Y chromosome of the child showed no deletion and mutation of SRY gene. The result of M-FISH of the baby was 45, X, dic(Y; 15)(p11.3; p11.2).ish dic(Y; 15)(wcp 1-22, wcp XY). Combined with the above examinations, it could be determined that the child was a dicentric chromosome carrier caused by balanced translocation of Y chromosome and chromosome 15, which was inherited from his father. The karyotype of the child was finally diagnosed with 45, X, dic(Y; 15)(p11.3; p11.2)pat, and the gender of the child was male.

Karyotype analysis is an important examination for children with hypospadias. Combined use of multiple genetic techniques is of great significance for differential diagnosis of chromosomal structural rearrangement, which contributes to reduce misdiagnosis.