Genomic organization, physical mapping, and involvement in Yq microdeletions of the VCY2 (BPY 2) gene

VCY2 is a gene positioned within the AZFc locus of the Y chromosome, a region frequently deleted in infertile males. To investigate the involvement of this gene in idiopathic male infertility, we studied its genomic organization and localization. Analysis of the genomic structure demonstrated that the VCY2 gene is composed of 9 exons spanning 21 kb. FISH analysis on interphase nuclei with specific probes for exons 4-6, 7, and 8 demonstrated the presence of a single gene copy, and Fiber-FISH on relaxed chromatin indicated that VCY2 is located within the DAZ gene cluster. PCR, Southern blot, and FISH analysis on infertile patients with Yq microdeletions demonstrated the absence of VCY2 in all cases where deletions involved the DAZ gene, raising the question about the role of the VCY2 gene loss in the phenotype reported for DAZ-deleted patients.