ALADH, or Aminolevulinate dehydratase, is a human gene encoded by ALAD. It may also be known as: Delta-aminolevulinic acid dehydratase; Porphobilinogen synthase; PBGS. The encoded protein is an enzyme with an amino acid length of 330 and a mass of 36.3 kDa. Other isoforms may exist. ALADH is a member of the ALAD family. Homologs of this gene exist in other organisms, including: Mouse, Rat, Zebrafish, Frog, Chicken.