ALT Can we obtain genetic information from DNA without testing it directly? The DNA code gives important information about how your body works, but DNA is complex and it is expensive to test. We looked at whether we could use DNA information that is already available from previous studies – including up to half a million people – to get information about one gene, called filaggrin. We showed that this is possible and it’s a practical way to obtain genetic information from research participants in a cost-effective way.