However, by analyzing the mRNA levels of the various genes involved in mitochondrial dynamics, the expression of proteins related to mitochondrial fission, such as Drp1 and Fis1, was found increased, while the expression of fusion proteins (Mfn1, Mfn2, OPA1), was decreased proportionately with the stage of HD [232]. Here, MFN1 is linked to Huntington disease.