Most liver epithelial cell lines from C3B6F1 mice exhibit parentally-biased loss of heterozygosity at the Lci (Liver cell immortalization) locus on chromosome 4.

Liver epithelial cell lines established from F1 animals generated from hepatocarcinogen-sensitive C3H/HeJ and -resistant C57BL/6J mice were analysed for loss of heterozygosity at more than 60 simple sequence repeat marker loci distributed over all of the autosomal chromosomes. Nineteen of 20 clonal cell lines showed loss of heterozygosity at a chromosome 4 locus, designated Lci (Liver cell immortalization) and in most of the cases (18 of 19), alleles from the hepatocarcinogen-resistant parental strain, C57BL/6J, were lost. Detailed deletion mapping localized the putative suppressor gene for immortalization to within a 2 cM interval which includes a cluster of genes for gap junctional proteins. We also observed a loss of heterozygosity on chromosomes 7, 14, or 17 in more than 50% of the cell lines.