Most of our readers will know that all Nature Genetics research papers are published online on Sundays, in advance of print publication. Starting next Monday, and on every Monday, Free Association will feature links to the abstracts of that week’s papers, as a way of inviting discussion (see “The Sunday Papers” heading).

On rare occasions we will publish a paper online mid-week, if it is particularly timely for an upcoming conference at which the data in such a paper are sure to attract attention. This afternoon we have posted a paper by Anna Helgadottir et al., entitled “A variant of the gene encoding leukotriene A4 hydrolase confers ethnicity-specific risk of myocardial infarction”. This papers reports an association study for a common, complex disease, and shows the same haplotype conferring differential risk on two populations. It’s a top-flight conversation piece.