Rare variants in MUC17 are also weakly associated with myelitis (SKAT P = 0.0132) and optic neuritis (SKAT P = 0.0384) in Genebass (https://genebass.org/), suggesting that MUC17 rs78263695 variant, possibly together with other incomplete-penetrant variants, may modify MS risk in this family. The gene discussed is MUC17; the disease is optic neuritis.