Leukodystrophy, Hypomyelinating, 19, Transient Infantile, also known as hld19, is related to hypomyelinating leukodystrophy 19. An important gene associated with Leukodystrophy, Hypomyelinating, 19, Transient Infantile is TMEM63A (Transmembrane Protein 63A). Affiliated tissues include brain and spinal cord, and related phenotypes are delayed cns myelination and pendular nystagmus