Characterization of novel genes in AZF regions

The long arm of the Y chromosome contains genes mapped in loci involved in male infertility, short stature and gonadoblastoma. However, many of these genes have not been fully characterized, and are not currently investigated in patients affected by such diseases. We report a study aimed to the genomic characterization of 5 genes mapped within the Y chromosome: BPY2, PRY, TTY1, TTY2, and VCY. Exon-intron boundaries were detected for each gene, and PCR analysis was carried out to investigate the involvement of these genes in different re-arrangements of the Y chromosome. It was found that BPY2 and PRY are lost in some infertile patients with Yq microdeletions, suggesting that they could play a role in male gametogenesis. On the other hand, these patients retain some copies of TTYI and TTY2 genes, due to the presence of copies in Yp, and of VCY, which has homologous copies on the X chromosome. On the basis of their localization, these genes could be candidate for the gonadoblastoma locus (TTY1, TTY2) and for the control growth locus (VCY).