Molecular cloning of human G alpha q cDNA and chromosomal localization of the G alpha q gene (GNAQ) and a processed pseudogene

Genomics. 1995 Dec 10;30(3):470-75. doi: 10.1006/geno.1995.1267.


G alpha q is the alpha subunit of one of the heterotrimeric GTP-binding proteins that mediates stimulation of phospholipase C beta. We report the isolation and characterization of cDNA clones from a frontal cortex cDNA library encoding human G alpha q. The encoded protein is 359 amino acids long and is identical in all but one amino acid residue to mouse G alpha q. Analysis of human genomic DNA reveals an intronless sequence with strong homology to human G alpha q cDNA. In comparison to G alpha q cDNA, this genomic DNA sequence includes several small deletions and insertions that alter the reading frame, multiple single base changes, and a premature termination codon in the open reading frame, hallmarks of a processed pseudogene. Probes derived from human G alpha q cDNA sequence map to both chromosomes 2 and 9 in high-stringency genomic blot analyses of DNA from a panel of human-rodent hybrid cell lines. PCR primers that selectively amplify the pseudogene sequence generate a product only when DNA containing human chromosome 2 is used as the template, indicating that the authentic G alpha q gene (GNAQ) is located on chromosome 9. Regional localization by FISH analysis places GNAQ at 9q21 and the pseudogene at 2q14.3-q21.

MeSH terms

  • Animals
  • Base Sequence
  • Chromosome Mapping
  • Chromosomes, Human, Pair 2 / genetics*
  • Chromosomes, Human, Pair 9 / genetics*
  • Cloning, Molecular
  • DNA, Complementary
  • GTP-Binding Protein alpha Subunits, Gs / genetics*
  • Humans
  • Hybrid Cells
  • Mice
  • Molecular Sequence Data
  • Pseudogenes / genetics*
  • Sequence Homology, Amino Acid
  • Sequence Homology, Nucleic Acid


  • DNA, Complementary
  • GTP-Binding Protein alpha Subunits, Gs