more problems for the "directed mutation" zealots

This research may be the latest nail in the coffin of 'directed mutation' it's by no means the first:D. I. Andersson, E. S. Slechta, and J. R. Roth. Evidence that gene amplification underlies adaptive mutability of the bacterial lac operon. Science 282 (5391):1133-1135, 1998."Apparent directed mutability, its recombination requirement, and its apparent independence of cell growth are all accounted for by the model. Evidence is provided for the required residual function and gene amplification"E. S. Slechta, J. Harold, D. I. Andersson, and J. R. Roth. The effect of genomic position on reversion of a lac frameshift mutation (lacIZ33) during non-lethal selection (adaptive mutation). Mol.Microbiol. 44 (4):1017-1032, 2002.E. S. Slechta, J. Liu, D. I. Andersson, and J. R. Roth. Evidence That Selected Amplification of a Bacterial lac Frameshift Allele Stimulates Lac(+) Reversion (Adaptive Mutation) With or Without General Hypermutability. Genetics 161 (3):945-956, 2002.