GNAQis 359 amino acids long and is identical in all but 1 amino acid residue to the Mouse protein. Analysis of human genomic DNA revealed an intronless sequence with strong homology to human GNAQ cDNA. In comparison to GNAQ cDNA, this genomic DNA sequence included several small deletions and insertions that altered the reading frame, multiple single based changes, and a premature termination codon in the open reading frame, all hallmarks of a processed pseudogene. Probes derived from human GNAQ cDNA sequence mapped both chromosomes 2 and 9 in higher constringency genomic blot analyses of DNA from a panel of human/rodent hybrid cell lines.