Objectives To inverstigate the effect of gr/gr subdeletion in partial AZFc deletion on human spermatogenesis.Methods We assessed The prevalence of gr/gr deletion in a population of both normospermic and infertile men with severe impairment of spermatogenesis were assessed,the contribution of these gr/gr deletion to male infertility was determined.A combined methodological approach that included the detection of the different DAZ gene copies by sequence nucleotide variant (SNV) analysis and AZFc-specific sequence tagged site (STS) markers was used.Results Type of gr/gr deletion was detected in 27 cases of 278 males with oligozoospermic and 17 cases of 220 donors.There was no difference in the prevalence of gr/gr deletion comparing oligozoospermic and normospermic groups (P =0.438).Of the 27 men with the gr/gr deletion,23 cases exhibited the doublet deletion of DAZ1/DAZ2 and 1 case showed the DAZ3/DAZ4 deletion.In the normozoospermic population,16 cases of gr/gr-DAZ3/DAZ4 deletions and one gr/gr-DAZ1/DAZ2 deletion were found.There was a significant difference when comparing gr/gr-DAZ1/DAZ2 deletions vs.gr/gr-DAZ3/DAZ4 deletions in the oligozoospermic and normospermic groups (P =0.000).Conclusions The gr/gr-DAZ3/DAZ4 deletion may not be sufficient to cause spermatogenic impairment.In addition,gr/gr microdeletions,which involve the DAZ1/DAZ2 region,may be a main cause of low sperm concentration and spermatogenic failure in the south chinese population.