Cloning and characterization of a novel member of human beta-1,4-galactosyltransferase gene family

By using the EST strategy for identifying novel members belonging to homolo gous gene families, a novel full-length cDNA encoding a protein significant ly homologous to UDP-Gal: N-acetylglucosamine beta-1,4-galactosyl-transfera se (GalT) was isolated from a human testis cDNA library. A nucleotide seque nce of 2 173 bp long was determined to contain an open reading frame of 1 0 32 nucleotides (344 amino acids). In view of the homology to members of the galactosyltransierase gene family and especially the closest relationship to Gallus gallus GalT type I (CK I), the predicted product of the novel cDN A was designated as human P-l, 4-galactosyltransferase homolog I (HumGT-H1) . Its mRNA is present in different degrees in 16 tissues examined. Southern analysis of human genomic DNA revealed its locus on chromosome 3.