The Saccharomyces cerevisiae pol2-S476L mutation mimicking human POLE-S461L causes a mutator phenotype in haploid strains when no wild-type POL2 is present.
References:
Ostroverkhova, D. et al. DNA polymerase ε and δ variants drive mutagenesis in polypurine tracts in human tumors. Cell Rep 43, 113655 (2024) https://pubmed.ncbi.nlm.nih.gov/38219146/