According to published literature of microdeletions and rearrangements in the Xq28 region containing the MAMLD1-MTM1-MTMR1 genes [see Table 3 and [1, 2, 28–30]], which causes myopathy for the involvement of the MTM1 gene, it appears for the DSD phenotype that the C-terminal region of the MAMLD1 gene is critical for abnormal sex development [29]. The gene discussed is MTMR1; the disease is disorder of sexual differentiation.