Genetic screening distinguishes the MutSβ complex in actively growing yeast. (A) The specific genetic interactions of fission yeast msh2Δ and msh3Δ are similar and distinct from msh6Δ. NAT-marked deletions (for example, msh2Δ::NAT) were placed in the context of 1,955 non-essential fission yeast gene deletions and relative colony size used to derive scores covering each negative (≤ -2.5) genetic interaction (see Methods). Shown are a representative set of 53 genetic relationships expressed by heat map (key below) and identified by their systematic ID and standard Sp/Sc (if present) gene names. Blue, orthologous relationships also tested in budding yeast (see Figure3). Red, Sp-specific orphans. Given the high rate of replication-errors in MMR-gene mutants ,, multiple queries of each deletion were screened to obtain a high confidence dataset. The independent accumulation of confounding secondary mutations may explain why the specific genetic interactors from this study are not described in the available high-throughput datasets that relied on single deletion clones ,,. (B) Distribution plot of Pearson correlation co-efficients (CCs) comparing the genetic interaction profiles of msh2Δ and msh3Δ within a (953×1,955) dataset. Red dots indicate the CC of each genetic screen to a specific msh2Δ or msh3Δ query clone: shaded area highlights screens that would be classed as significantly correlated (CC ≥0.2).