Controls were the same as those used in the GenRED GWAS analysis.4 Details are described elsewhere.9, 13 They were recruited for MGS by a survey research company (Knowledge Networks, Inc., Menlo Park, CA) from a nationally-representative internet-based panel that was selected by random digit dialing. Participants had completed an online version of the Composite International Diagnostic Interview-Short Form (CIDI-SF)17 for lifetime history of common mood, anxiety and substance use disorders. They consented to anonymization and deposition of their DNA and clinical information in the NIMH repository for use in any medical research. The 1,636 European-ancestry controls used here had no lifetime history of MDD (or of recurrent depression missing MDD by one criterion) by CIDI-SF criteria (which over-diagnose MDD18). The MGS collaboration gave permission for us to use genotypes for the part of the control sample that is still under a dbGAP publication embargo. Clinical and demographic characteristics are summarized in Table 1.
