Isolation of the mouse cDNA homologous to the human EXT1 gene responsible for Hereditary Multiple Exostoses.

We have cloned and sequenced the mouse cDNA homologous to the human Hereditary Multiple Exostoses (EXT1) gene. The mouse homolog shows 94% similarity at the nucleotide level and 99% similarity at the protein level compared to the human gene. The 5' UTRs are unusually conserved for non-coding sequences showing 94% similarity compared to 80% for the 3' UTRs. The high level of evolutionary conservation between the EXT1 proteins as well as the 5' UTR suggests that each plays an important and related role in both species.