Deletion of a DNA Polymerase β Gene Segment in T Cells Using Cell Type-Specific Gene Targeting

Deletion of the promoter and the first exon of the DNA polymerase β gene (pol β) in the mouse germ line results in a lethal phenotype. With the use of the bacteriophage-derived, site-specific recombinase Cre in a transgenic approach, the same mutation can be selectively introduced into a particular cellular compartment-in this case, T cells. The impact of the mutation on those cells can then be analyzed because the mutant animals are viable.