Consistent with this hypothesis, Hadziselimovic et al., showed that the expression of several transposon silencing genes, including DDX4, MAEL, MOV10L1, HILI, HIWI2, and TDRD9 genes was silenced or reduced in cryptorchid boys with high risk of azoospermia. The gene discussed is PIWIL4; the disease is Azoospermia.