Sequencing the genome of an antibiotic-resistant microbe can identify the most dangerous isolates, reports a team led by Ruth Massey at the University of Bath, UK.

Her group studied 90 isolates of methicillin-resistant Staphylococcus aureus (MRSA) that had varying levels of ability to stick to and kill cultured human cells. The researchers sequenced the isolates, and conducted a genome-wide association study to identify 121 genetic changes, including additions or deletions of DNA, that were linked to this toxicity.

A set of 50 of these variants could predict the most and least toxic of 30 of the isolates, although it was unable to predict the medium-toxicity isolates with any accuracy.

Genome Res. http://dx.doi.org/10.1101/gr.165415.113 (2014)