Extending the clinical and mutational spectrum of TRIM32-related myopathies in a non-Hutterite population

TRIM32-related myopathies represent a phenotypic spectrum of a rare autosomal recessive muscle disorder. The disease is described as a mild and progressive myopathy without characteristic clinical features. Originally classified as limb-girdle muscular dystrophy (LGMD) 2H (OMIM #254110), the disorder was first identified in the Hutterite population and the homozygous TRIM32 founder mutation, p.Asp487Asn, was identified as the cause of this disease. Only seven patients with definite non-Hutterite TRIM32-related myopathy have been reported in the literature. Apart from two missense mutations residing in the NHL repeats of TRIM32, only deletions, frameshift and nonsense mutations have been reported. Having applied next generation sequencing technologies to over 1000 patients with suspected genetic muscle disorders, the authors present nine patients with TRIM32-related myopathies and three patients with a homozygous TRIM32 variant of unknown significance (VUS).

Johnson K, De Ridder W, Töpf A, et al. Extending the clinical and mutational spectrum of TRIM32-related myopathies in a non-Hutterite population. J Neurol Neurosurg Psychiatry. 2018 Jun 19. pii: jnnp-2018-318288.