Aminoacyl-tRNA synthetases (ARSs) are enzymes that attach amino acids to their cognate tRNAs during protein synthesis. Several ARSs assemble into a large complex known as the multi-tRNA synthetase complex (MSC), whose physiological function remains incompletely understood. To gain insight into the role of the MSC, we surveyed genetic diseases caused by ARS variants and identified hypomyelinating leukodystrophy (HLD) as a disorder associated with defects in several MSC-associated ARSs, but not in non-MSC ARSs. HLD, characterized by defective central nervous system myelination and neurodevelopmental impairment, is caused by biallelic pathogenic variants in MSC components, including EPRS1, AIMP1, AIMP2, and RARS1. Because RARS1 is positioned at the terminal end of the MSC, we hypothesized that pathogenic RARS1 variants may alter its association with the complex. Consistent with this idea, several RARS1 mutants showed altered MSC binding patterns that appeared to correlate with disease severity. In addition, pharmacological inhibition of RARS1 reduced differentiation in an oligodendrocyte cell model. Ongoing studies aim to further examine whether altered association of RARS1 with the MSC contributes to myelination defects.