Using mutants 2 and 3 from Problem 19, following mixed infection on E. coli B, progeny viruses were plated in a series of dilutions on both E. coli B and K12 with the following results. Another mutation, 6, was tested in relation to mutations 1 through 5 from Problems 18–20. In initial testing, mutant 6 complemented mutants 2 and 3. In recombination testing with 1, 4, and 5, mutant 6 yielded recombinants with 1 and 5, but not with 4. What can you conclude about mutation 6?

Key Concepts

Complementation

Complementation occurs when two different mutations in separate genes can restore a common phenotype when present together. In the context of the question, mutant 6's ability to complement mutants 2 and 3 suggests that these mutants likely affect different genes, allowing for functional restoration when combined.

Recombination

Recombination is a genetic process where segments of DNA are rearranged, leading to new allele combinations. The results indicate that mutant 6 can recombine with mutants 1 and 5, suggesting that these mutations may be in the same genetic pathway or region, while the lack of recombination with mutant 4 implies a distinct genetic separation.

Mutant Analysis

Analyzing mutants helps in understanding gene function and interactions. In this scenario, the behavior of mutant 6 in relation to other mutants provides insights into its genetic relationship, indicating that it may share functional pathways with some mutants while being distinct from others, which is crucial for mapping genetic interactions.