48,XYYY: A Rare Case Report

Area of Science:

• Genetics
• Pediatrics
• Urology

Background:

• Hypospadias and cryptorchidism are common congenital anomalies in pediatric urology.
• Chromosomal abnormalities can present with a wide spectrum of phenotypic features.
• Mosaicism, the presence of two or more cell lines with different genotypes, can occur in chromosomal disorders.

Observation:

• A 4-year-old male presented with hypospadias and right-sided cryptorchidism.
• Karyotype and Fluorescence In Situ Hybridization (FISH) analysis revealed a mosaic chromosomal pattern: 48,XYYY (73%), 47,XYY (7%), 46,XY (7%), and 45,X (13%).
• No other significant phenotypic abnormalities were noted besides the urogenital anomalies.

Findings:

• The patient exhibited a rare mosaic chromosomal abnormality involving supernumerary Y chromosomes and a 45,X cell line.
• The clonal nature of the abnormality was confirmed, but inheritance was excluded by normal parental and sibling karyotypes.
• The findings highlight the variability in phenotypic expression of chromosomal abnormalities.

Implications:

• This case underscores the importance of comprehensive genetic analysis in pediatric patients with congenital anomalies, even with limited phenotypic presentation.
• Management recommendations included genetic counseling and surgical correction of hypospadias and cryptorchidism.
• Further research into the developmental impact and long-term outcomes of such rare chromosomal mosaicisms is warranted.