GENETIC-CHARACTERIZATION OF THE BOVINE LEUKEMIA INHIBITORY FACTOR (LIF) GENE - ISOLATION AND SEQUENCING, CHROMOSOME ASSIGNMENT AND MICROSATELLITE ANALYSIS

The bovine leukaemia inhibitory factor was isolated from a phage libra ry and sequences for the gene, in addition to 1213 bp of 5' and 432 bp of 3' sequences, were obtained and compared with other mammalian leuk aemia inhibitory factor genes. Comparisons indicated an;ino acid homol ogies ranging from 89.6% to 77.2% with the human and mouse homologues, respectively, Analysis of 500 bp of 5' regulatory regions indicated h omologies ranging from 83.6% to 74.4% with the corresponding human and sheep sequences, respectively. Additionally, bovine leukaemia inhibit ory factor-specific primers were prepared, and a panel of bovine x ham ster somatic cell lines were analysed by the polymerase chain reaction (PCR). Data indicated 93% concordance of leukaemia inhibitory factor with aldehyde dehydrogenase 2 located an bovine chromosome 17, and con cordance of 81% with myelin basic protein situated on bovine chromosom e 24. Southern analysis of selected hybrids confirmed the PCR results, thus conclusively assigning the bovine leukaemia inhibitory factor ge ne to chromosome 17. Sequence analysis also revealed a microsatellite in intron 2 of the bovine leukaemia inhibitory factor, Analysis of thi s region by PCR in 22 unrelated Bos taurus and 19 unrelated Bos indicu s cattle detected nine different alleles, Polymorphic information cont ent values were 0.53 and 0.80 in B. taurus and B. indicus, respectivel y. Additionally, the same leukaemia inhibitory factor primers successf ully detected allelic variants at this locus in Bos javanicus, Bos gua rus and Bison bison but not in Odocoileus virginianus.