As DNA sequencing technology has improved over recent years, operator time has become the rate-limiting factor for mutation detection and error checking, and hence a large determinant of the cost of mutation analysis. GeneScreen is a new desktop computer programme that facilitates rapid analysis of large batches of capillary electropherograms, identifying sequence variants for operator verification and automated annotation and database export. It is freely available and compares well in performance with expensive commercial alternatives. (By Dr. Ian Carr, http://jmg.bmj.com/content/early/2010/10/29/jmg.2010.082081.abstract?papetoc )