A yeast‐based complementation assay elucidates the functional impact of 200 missense variants in human PSAT1

Defects in serine biosynthesis resulting from loss of function mutations in PHGDH , PSAT1, and PSPH cause a set of rare, autosomal recessive diseases known as Neu‐Laxova syndrome (NLS) or serine‐deficiency disorders. The diseases present with a broad range of phenotypes including lethality, severe neurological manifestations, seizures, and intellectual disability. However, because L‐serine supplementation, especially if started prenatally, can...