Assignment of the human gamma-glutamyl transferase gene to the long arm of chromosome 22.
We have determined the chromosomal location of the human gene for gamma-glutamyltransferase (GGT). This study was done by in situ hybridization of human metaphase spreads with a rat cDNA probe specific for this enzyme and constructed from two clones previously characterized in our laboratory. The final construct had a 1.6-kb-long insert covering 92% of the coding sequence for GGT. The new insert was also freed of any GC tails introduced for the cDNA cloning, because we observed that these sequences were responsible for a high background. Using this probe for the analysis of 136 human metaphase spreads, we observed a strong specific signal on chromosome 22 at the interface of q111-112 and a minor peak in q131. Thus GGT might represent a new marker for the study of certain diseases which have chromosomal abnormalities at these loci.
D002871:Chromosome Banding; D002874:Chromosome Mapping; D002892:Chromosomes, Human, Pair 22; D004247:DNA / Q000235:genetics; D006801:Humans; D007621:Karyotyping; D009693:Nucleic Acid Hybridization; D005723:gamma-Glutamyltransferase / Q000235:genetics*
D004247:DNA; D005723:gamma-Glutamyltransferase