DRP2 and X-linked agammaglobulinemia: As an example, whole exome sequencing of a six boys of four unrelated families with X-linked agammaglobulinemia and Mohr–Tranebjaerg syndrome revealed a large deletion in all patients, and in one case deletion included the genes TIMM8A, TAF7L, and DRP2. Of note, the cases suffered from neurological impairments and sensorineural deafness (19).