HAPLN1 and Charcot-Marie-Tooth disease: We previously established in-house enzyme-linked immunosorbent assays (ELISAs) to measure serum levels of autoantibodies against AGR2 (anti-AGR2), HAPLN1 (anti-HAPLN1), IGFBP5 (anti-IGFBP5), and TYMS (anti-TYMS) in dogs with CMT.