Interestingly, external validation showed that low expression of seven genes (DDX3Y, EIF1AY, RPS4Y1, SMCY, USP9Y, UTY, and ZFY) had an adverse effect on survival for MM patients and three genes (BTN3A1, MAP3K3, and UBA7) were correlated with immune infiltrates in multiple cancer types. Here, USP9Y is linked to Miyoshi myopathy.