Forward genetic screen based on chemically induced mutations has advantages in the unbiased identification of novel genes and gene functions. The most commonly used chemical mutagen is ethylmethane sulfonate (EMS), which induces random point mutations by nucleotide substitution. Acquisition of this collection is ongoing. More stocks will be added as they become available.

The current collection includes a set of X chromosome lethals generated by Hugo Bellen's lab as part of a forward genetic screen utilizing low concentrations of EMS to minimize lethal hits per chromosome.