Open AccessMitotic recombination is responsible for the loss of heterozygosity in cultured murine cell lines.
Author(s) -
F. Kenneth Nelson,
Wayne N. Frankel,
T. V. Rajan
Publication year - 1989
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.9.3.1284
Subject(s) - biology , mitotic crossover , loss of heterozygosity , locus (genetics) , genetics , centromere , microbiology and biotechnology , mutant , allele , mitosis , genotype , recombination , chromosome , gene
Heterozygous mammalian cell lines normally express both parental alleles at most autosomal loci. However, mutants can be isolated that fail to express one of the alleles. Using a murine pre-B cell line that is heterozygous for several loci on chromosome 12, including one encoding the cell surface antigen Ly-18, we found that one of the two Ly-18 antigenic forms was lost at a rate of 1.5 x 10(-5) per cell per generation. Molecular analysis revealed that a genetic marker distal to Ly-18 became homozygous. Analysis of the genotype of the mutants at the rDNA cluster, located close to the centromere, strongly suggests that the mutants arose by mitotic recombination within this multicopy locus.