Intranuclear inclusions in oculo-pharyngo-distal myopathy (OPDM)

Oculopharyngodistal myopathy (OPDM) is an ultra-rare autosomal dominant neuromuscular disease in which abnormal CGG-like nucleotide repeats have been identified in three genes (NOTCH2NLC, GIPC1, LRP12). Japanese researchers have studied the presence of p62-labeled nuclear inclusions in skin samples:

  • these inclusions are similar to those described in intranuclear inclusion disease (NIID), which doesn’t include myopathy;
  • in patients mutated for NOTCH2NLC, these inclusions are also found in glandular cells, adipocytes and fibroblasts present in the skin;
  • skin biopsy is an interesting tool in OPDM both for diagnosis and for research.


Intranuclear inclusions in skin biopsies are not limited to neuronal intranuclear inclusion disease but can also be seen in oculopharyngodistal myopathy. Ogasawara M, Eura N, Nagaoka U, et al. Neuropathol Appl Neurobiol. 2021 Dec 19.