Mutations in seven genes have been identified so far as causing NM: actin alpha 1 (ACTA1), alpha-tropomyosin-3 and beta-tropomyosin (TPM3 and TPM2), nebulin (NEB), troponin T type 1 (TNNT1), cofilin-2 (CFL2), and kelch repeat and BTB (POZ) domain containing 13 (KBTBD13) genes. The gene discussed is TPM2; the disease is nemaline myopathy.