SPTBN2 and distal myopathy with posterior leg and anterior hand involvement: Moreover, a drug developed for SCA5 may also be useful in other rare diseases, such as Focal Segmental Glomerulosclerosis, Congenital Macrothrombocytopenia, Otopalatiodigital Syndrome, Autosomal Dominant Atelosteogenesis, William’s Distal Myopathy, which have also been linked to “gain-of-function” ABD mutations in spectrin-related proteins, including filamin (5, 6, 7) and α-actinin (2, 3, 4).