Mutations in C19orf12 and intronic repeat expansions in C9orf72 not observed in Iranian Parkinson's disease patients

Various neurodegenerative disorders share some clinical features that sometimes renders differential diagnosis challenging. Genetic-based classification also has limitations as mutations in the same gene are sometimes associated with different clinically based diagnoses. In this light, we screened the C19orf12 neurodegeneration with brain iron accumulation (NBIA) causing gene and the C9orf72 intronic expansion mutation that is cause of amyotrophic lateral sclerosis in 186 Iranian Parkinson's disease (PD) patients. C19orf12 has previously been screened in PD patients in only one study, and to the best of our knowledge neither gene has ever been screened in a PD cohort from a Middle East population. The study was justified because mutations in C19orf12 had previously been shown to be common in Iranian neurodegeneration with brain iron accumulation patients and all the patients with mutations in this gene had exhibited Parkinsonism features. The C9orf72 intronic expansion mutation was screened because the mother of an Iranian amyotrophic lateral sclerosis patient with the expansion who had been diagnosed with PD also harbored the expansion. The screenings did not identify disease causing variations in either of the genes among the PD patients screened.