Genes for HMG-CoA reductase and serotonin 1a receptor are on mouse chromosome 13.

3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase is the key regulatory enzyme for cholesterol biosynthesis. The human gene (HMGCR) has been assigned to the q13.3-q14 region of chromosome 5 (HSA5). We have now mapped the mouse gene Hmgcr to mouse chromosome 13 by Southern analysis of somatic cell hybrids. We also report the mapping to mouse chromosome 13 of the murine homolog of the gene for an intronless beta 2-adrenergic-like receptor, which is also located on human chromosome 5 region q11.2-q13 and has recently been identified as the serotonin 1a receptor. Our results confirm the existence of an evolutionarily conserved syntenic group of genes on the proximal long arm of HSA5 and on MMU13 that also includes the loci for arylsulfatase B, hexosaminidase B and dihydrofolate reductase.