Brachypodium distachyon (Poaceae) is now a widely accepted model grass. Its favourable cytogenetic features and advanced molecular infrastructure make it also a useful model system in mutagenesis studies.
Kus et al. use fluorescent in situ hybridisation with repetitive DNA sequences and Bacterial Artificial Chromosome (BAC)-based chromosome-specific probes (mcFISH) to qualitatively and quantitatively analyse the composition and origin of micronuclei after maleic hydrazide or X-radiation treatment. They demonstrate that most of the micronuclei originate from large, acentric fragments. They also show statistically significant differences among the analysed samples, most notably displaying some overrepresentation of micronuclei from chromosome Bd1.