SOD2 and Infertility: To clarify the associations of sperm capacity and gene mutation (ATPase6 (m.T8993G) and SNPs of UCP2 (G-866A, rs659366), MnSOD (C47T, rs4880), CAT (C-262T, rs1001179), and hOGG1 (C1245G, rs1052133)), a total of 216 sperm samples were categorized into three groups, i.e., fertile subjects (control group), infertile subjects with more than 50% motility, and infertile subjects with less than 50% motility.