Serine palmitoyltransferase, which consists of two different subunits, is the initial enzyme in sphingolipid biosynthesis. It converts L-serine and palmitoyl CoA to 3-oxosphinganine with pyridoxal 5'-phosphate as a cofactor. The product of this gene is the long chain base subunit 1 of serine palmitoyltransferase. Mutations in this gene were identified in patients with hereditary sensory neuropathy type 1. Alternatively spliced variants encoding different isoforms have been identified.
The SPTLC1 cDNA contains an open reading frame of 1,422 nucleotides and encodes a 473-amino acid protein . A search of the UniGene database identified corresponding cDNA clones expressed in 29 different tissues, indicating that SPTLC1 is ubiquitously expressed.