Further, overexpression of ASFMR1 and long non-coding RNA have previously been reported in PM individuals,66 and have also been associated with parkinsonism and mitochondrial dysfunction.24 Future studies should explore the contribution of the aforementioned pathways as alternative explanations for the relationships observed in this study between FMR1 intron 1 methylation and phenotype measures. This evidence concerns the gene FMR1 and Parkinson disease.