Moreover, 29.8% (31/104) of patients had no associated gene variants such as CFTR, ADGRG2, PANK2, SLC9A3, SCNN1B and CA12, suggesting that there may be unknown gene variants or pathogenic mechanism in CAVD, which need to be further studied. The gene discussed is PANK2; the disease is congenital bilateral aplasia of vas deferens from CFTR mutation.