ALAD, Official Symbol ALADprovided by HGNC Official Full Name aminolevulinate dehydrataseprovided by HGNC Primary source HGNC:HGNC:395 See related Ensembl:ENSG00000148218 MIM:125270; AllianceGenome:HGNC:395 Gene type protein coding RefSeq status REVIEWED Organism Homo sapiens Lineage Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo Also known as PBGS; ALADH Summary The ALAD enzyme is composed of 8 identical subunits and catalyzes the condensation of 2 molecules of delta-aminolevulinate to form porphobilinogen (a precursor of heme, cytochromes and other hemoproteins). ALAD catalyzes the second step in the porphyrin and heme biosynthetic pathway; zinc is essential for enzymatic activity. ALAD enzymatic activity is inhibited by lead and a defect in the ALAD structural gene can cause increased sensitivity to lead poisoning and acute hepatic porphyria. Alternative splicing of this gene results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Dec 2015] Expression Ubiquitous expression in adrenal (RPKM 60.0), liver (RPKM 56.7) and 25 other tissues See more Orthologs mouse all