Structure and organization of a human glutathione transferase A4 pseudogene

We have isolated and characterized a new human glutathione transferase A4 g ene from a yeast artificial chromosome (YAC) containing several other GST a lpha genes and pseudogenes. A mGSTA4 cDNA probe was used to screen the YAC phage sublibrary and revealed four positive contig clones. These phage clon es were subjected to exon trapping to identify a potentially new hGSTA4 gen e. Four potential exons were isolated, including exons 3, 4, 6 and 7. Furth er in silico analysis of high throughput genome sequences revealed the posi tion of exons 2 and 5. Both exon sequence and reverse transcription-polymer ase chain reaction on human tissues analyses support the view that this gen e would not produce a functional enzyme and, therefore, is a pseudogene we termed, h2GSTA4P. (C) 2001 Elsevier Science Ireland Ltd. All rights reserve d.