Molecular characterization of oculopharyngodistal myopathy (OPDM) and mimicking disorders

Oculopharyngodistal myopathy (OPDM) is a rare, progressive inherited muscle disease involving the ocular, pharyngeal, and distal muscles. It is reported more frequently in Turkish, Japanese, and Chinese than in other communities. There were not any genes associated with OPDM since 2019. Although four different genes were identified between August 2019-November 2022 related to OPDM, none of the genes still cover majority of the patients. The aim of this thesis is to conduct molecular characterization of patients who admitted to Koç University Hospital Center for Muscle Diseases and were clinically diagnosed with OPDM. Seven cases with a clinical diagnosis of OPDM were referred to the medical genetics department between March 2018-2020. Four cases had a definite molecular diagnosis of the diseases in differential diagnoses, whereas the remaining three patients' molecular diagnoses were not definite. It has been shown that patients clinically followed up on OPDM should primarily be examined at the molecular basis for diseases in the differential diagnosis list. Four out of seven patients were diagnosed in a similar fashion. All studies including whole-genome sequencing were performed on one out of the three patients without a molecular diagnosis, and for this specific patient genetic etiopathogenesis still could not be clarified. Therefore, it is considered that genetic analysis should be studied more extensively in a genomic and functional manner with a wider gene pool through international teams.