Mutation monitoring

Although most in situ monitoring with plants occurs in controlled environments, it has also been proposed that measurements of frequencies of chromosomal aberrations in wild populations can be useful in mutational monitoring.209 ... 

Before considering specific possibilities, I should like to list some of the criteria by which a mutation-monitoring system in man might be judged. It may be that no system will work. Or it may be that no system is worth the cost and that the effort might better be allocated elsewhere, e.g., to a more strenous attempt to detect mutagens in advance. 

Here are some of the questions to be asked of a mutation-monitoring system ... 

A combination of efficient screening of a large number of somatic cells for chromosome breaks and an efficient way of measuring somatic point mutation rates—perhaps several systems involving different enzymes and with both forward and reverse mutations—seems to me to be the best nearfuture prospect for effective mutation monitoring. 

Crow (1971) has presented six criteria for a mutation-monitoring system, as follows ... 

Judged by these criteria, mutation monitoring by biochemical techniques is surely the best approach available today. To us, the most important reservation as of now is whether it would detect the important mutations. It is certainly not detecting mutations with gross phenotypic effects. But if the qualitative enzymatic changes with quan-... 

The cyan emitting form obtained by the mutation Y66W [10] deserves special attention, as it has led to the ECFP form (absorption at 437 nm, emission at 474 nm), whose variants are still intensively used as excitation energy donors in FRET imaging experiments for monitoring molecular associations in the living cell... 

Kunichika, K., Hashimoto, Y. and Imoto, T. (2002) Robustness of hen lysozyme monitored by random mutations. Protein Engineering, 15, 805-809. 

We have not directly determined the relative frequencies of frameshift mutations and other mutational events in comparison to the base substitution mutations. However, based on the high frequency of nonsense mutations (11%) among all lacl mutants induced by BPDE and because nonsense mutations are monitorable at less than one-fifth of the lacl codons and, even then, only via certain base pair substitutions, we believe that base substitutions account for a major fraction of mutations induced by BPDE. 

Both amber and ochre mutations can be generated at these sites, allowing both G C to T A and G C to C G transversions to be monitored. 

---