Genetic Studies Spermatogenic Failure

The proposed study is designed to test the following hypotheses: 1. Mouse autosomal or X-linked genes which are exclusively expressed in mouse spermatogonia are also spermatogonia-specific in human. 2. Severe spermatogenic defect, especially hypospermatogenesis or SCOS, is caused by an intrinsic defect in germ line stem cell or speramtogenia. 3. Spermatogonia-specific genes are caudate genes for human spermatogenic defect, especially for hypospermatogenesis or SCOS. 4. For a significant fraction of cases with severe spermatogenic defect, the sterile genes are transmitted via multifactorial inheritance mode. 5. For some cases with severe spermatogenic defect, mutations of spermatogonia- specific genes may be transmitted in the X-linked recessive, autosomal recessive, or autosomal dominant mode.