SPAG5 mRNA is over-expressed in peripheral blood leukocytes of patients with Down's syndrome and cryptorchidism.

Men with Down's syndrome (DS) have an increased risk of cryptorchidism, but the mechanisms causing its onset are not clear. Cryptorchidism causes a primary testiculopathy responsible for infertility. SPAG5 mRNA is predominantly expressed in testis in pachytene spermatocytes. This observation prompted us to evaluate the expression of SPAG5 gene in five DS men with cryptorchidism and five normal healthy men (controls) by quantitative real-time PCR in peripheral blood leukocytes. We found that SPAG5 is over expressed in the five men with DS and cryptorchidism compared with five age- and sex-matched normal controls. This finding suggests that the increased expression of this gene may play a pathogenic role durin testicular development in subjects with DS and cryptorchidism.