CDYI analysis in infertile patients with DAZ deletions

The DAZ(deleted in azoospermia) gene family is considered the major AZFc ("azoospermia factor" c) candidate responsible for male infertility, However, other genes have been recently mapped to this region and they could contribute to the AZFc phenotype, In particular, the testis-specific CDYI (chromadomain protein I) gene has one copy within the DAZ cluster and another one at its distal end. Therefore, this gene could be associated with the spermatogenic damage observed in DAZ-deleted patients since at least one CDYI copy is invariably absent in these patients. In this study, we investigated whether selected infertile patients affected by different testicutopathies caused by DAZ deletions retained CDYI and if a genotype-phenotype relation could be demonstrated, We found 3 out of 17 patients with absence of both CDYI copies, while 14 patients have only one CDYI copy absent, Two out of the 3 patients with deletion of both copies of CDYI were affected by severe hypospermatogenesis while one patient presented Sertoli cell-only syndrome. Therefore, there was no clear relation between genotype and phenotype, and the loss of the distal copy of CDYI does not seem to worsen the phenotype of infertile patients with deletion of the DAZ gene cluster. However, a possible contribution of CDYI in determining the spermatogenic alteration could not be excluded. (C) 2001, Editrice Kurtis.