⚁ 1.7 Hereditary inclusion body myopathy (hIBM).

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⚂ As different muscle diseases were being discovered, many of them had similar symptoms.
≻ At first, it was believed that several of these diseases were related to each other and where given very similar names.
≻ As time and research went on, it was discovered they have different causes and are different diseases.
≻ An example of this is hereditary inclusion body myopathy (hIBM).
≻≻ It was initially believed that it was directly related to inclusion body myositis, but it is now understood that these are a group of inherited muscle diseases caused by genetic mutations and they are not related to IBM.
≻≻ There was ongoing confusion because the names are very similar and it is now recommended that the name of each specific disease be used instead of the umbrella term hereditary inclusion body myopathy (hIBM).

⚃ Greenberg (2019) pointed out that it is a mistake to think IBM and hIBM reflect the same pathophysiological process that can either occur sporadically or be inherited: "IBM" is an entirely different disease than the group of diseases known as hereditary inclusion body myopathies, but often abbreviated as "hIBM."

⚃ The different forms of hereditary inclusion body myopathy are caused by mutations in different genes that can be passed from generation to generation.
≻ Examples:
≻≻ GNE myopathy (GNEM) / Distal myopathy with rimmed vacuoles (DMRV). Caused by autosomal mutations in the GNE gene. GNE myopathy and DMRV are the same entity (Broccolini and Mirabella, 2015).
≻≻ IBMPFD, hereditary inclusion-body myopathy with Paget's disease of bone and frontotemporal dementia. Mutations in the VCP gene are the main cause of IBMPFD.
≻≻ Hereditary inclusion body myopathy-joint contractures-ophthalmoplegia syndrome (HIBM3). Mutations in the MYH2 - myosin heavy chain 2 gene.