A pseudogene for human glutathione peroxidase

• Published in: Gene Vol. 122; no. 2; pp. 377 - 380
• Main Authors: Diamond, Alan M., Cruz, Rebecca, Bencsics, Craig, Hatfield, Dolph
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.12.1992; Amsterdam Elsevier; New York, NY
• Subjects: Base Sequence; Biological and medical sciences; Chromosomes, Human, Pair 21; cloning; Cloning, Molecular; DNA; evolution; Fundamental and applied biological sciences. Psychology; Gene; Genes. Genome; Glutathione Peroxidase - genetics; Humans; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Pseudogenes; retrotransposition; UGA: sequencing; ORF; Gene; nt; retrotransposition; kb; UGA: sequencing; evolution; cloning; bp; GPx; Glutathione peroxidase; Human; Pseudogene; Complementary DNA; Intron; Nucleotide sequence; Enzyme; Deletion; Homology; G21-Chromosome
• ISSN: 0378-1119; 1879-0038
• DOI: 10.1016/0378-1119(92)90230-M

Glutathione peroxidases (GPx) serve a bioprotective function in the reduction of peroxides to less toxic substances. Both cellular and secreted forms of the protein have been reported, as well a number of distinct cDNA sequences. Previous efforts have described three distinct loci on human chromosomes 3, 21 and X which hybridize to a GPX cDNA and these authors have speculated that only the chromosome 3 locus encodes a functional GPX gene. This conclusion was based on mapping studies showing a precise deletion of intron sequences in the GPX loci on chromosomes 21 and X despite strong conservation among these sequences in both the coding and 3′-untranslated regions. To pursue this issue, we have isolated the chromosome 21 GPX locus by molecular cloning and determined its nucleotide sequence. Consistent with the expectations of McBride et al. [Biofactors 4 (1988) 285-292], the sequence does reveal a highly conserved processed pseudogene. It is suggested that a retrotransposed copy of the GPX gene integrated into chromosome 21 and may have maintained activity prior to the accumulation of inactivating mutations.