DEGS1 and leukodystrophy, hypomyelinating, 18: In humans, bi-allelic mutations in DEGS1 cause hypomyelinating leukodystrophy-18 (HLD-18), a progressive, often fatal pediatric neurodegenerative disease marked by cerebral atrophy, white matter reduction, and hypomyelination (Dolgin et al., 2019; Karsai et al., 2019; Pant et al., 2019).