EFHC2 and myalgic encephalomeyelitis/chronic fatigue syndrome: The 13 genes are ABCC12, CFTR, CTAGE1, DAOA-AS1, EFHC2, FHL5, GRIK2, NAV3, SPO11, SYCP2, TAAR9, TPH2, and ZNF157. Among the 10 diseases, two are male-specific (male infertility and non-syndromic oligospermia), four affect males more than females (X-linked mental retardation, generalized epilepsy, Sezary syndrome, cutaneous T-cell lymphoma), three affect females more than males (chronic fatigue syndrome, panic disorder, and pseudoxanthoma elasticum), and one displays distinct disease characteristics between males and females (personality disorders).