Any mutagen that induces single basepair mutations or small deletions/insertions is effective for TILLING. EMS (Ethylmethane Sulphonate) is the mutagen we have employed, for the following reasons:
● Its effects have been well studied and it is known to generate almost exclusively G/C to A/T point mutations.
● These mutations may lead to a complete or partial loss of gene function or, less frequently, to some other alteration of normal gene function.
● Mutations are randomly distributed in the genome.
● A high degree of mutation saturation can be achieved with a mutagen like EMS that does not cause a lot of collateral DNA damage.
● For a review of the spectrum of mutations induced by EMS see: Greene EA, et al., 2003. Genetics 164:731-740.