PRKCB and Menkes disease: However, next-generation sequencing techniques have provided new information: rare variants segregating with familial MD in a family with the sequence similarity 136 member A (FAM136A), dystrobrevin α (DTNA), protein kinase C β (PRKCB), dermatopontin (DPT), and semaphorin 3D (SEMA3D) genes have been identified by exome sequencing [10,11,12].