The full text of this article is not available on the LRA. The published version can be found at http://www.blackwellpublishing.com/jeb_enhanced/\ud DOI: 10.1046/j.1420-9101.2001.00267.xSeveral important biological phenomena, including genetic recombination\ud and sexual reproduction, could have evolved to counteract genome contamination\ud by deleterious mutations. This postulate would be especially relevant if\ud it were shown that deleterious mutations interact in such a way that their\ud individual negative effects are reinforced by each other. The hypothesis of\ud synergism can be tested experimentally by crossing organisms bearing\ud deleterious mutations and comparing the ®tness of the parents and their\ud progeny. The present study used laboratory strains of the budding yeast\ud burdened with mutations resulting from absence of a major DNA mismatch\ud repair function. Only in one, or possibly two, crosses out of eight did ®tness of\ud the progeny deviate from that of their parents in a direction indicating\ud synergism. Furthermore, the distributions of progeny ®tness were not skewed\ud as would be expected if strong interactions were present. The choice of\ud experimental material ensured that genetic recombination was extensive, all\ud four meiotic products were available for ®tness assays, and that the mutations\ud were probably numerous. Despite this generally favourable experimental\ud setting, synergism did not appear to be a dominating force shaping ®tness of\ud yeast containing randomly generated mutations
To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.