This research has been conducted using the UK Biobank Resource under Application Number 12052.

The ALSPAC work is supported by a Medical Research Council program grant (MC_UU_12013/4 to D.M.E). The UK Medical Research Council and the Wellcome Trust (grant refs: 092731 and 102215/2/13/2) and the University of Bristol provide core support for ALSPAC. D.M.E. is supported by an Australian Research Council Future Fellowship (FT130101709). This publication is the work of the authors and D.M.E. will serve as guarantor for the contents of this paper. ALSPAC GWAS data was generated by Sample Logistics and Genotyping Facilities at the Wellcome Trust Sanger Institute and LabCorp (Laboratory Corporation of America) using support from 23andMe.

The ERF Study was supported by the joint grant from the Netherlands Organization for Scientific Research (NWO, 91203014), the Center of Medical Systems Biology (CMSB), Hersenstichting Nederland, Internationale Stichting Alzheimer Onderzoek (ISAO), Alzheimer Association project number 04516, Hersenstichting Nederland project number 12F04(2).76, and the Interuniversity Attraction Poles (IUAP) program. As a part of EUROSPAN (European Special Populations Research Network), ERF was supported by European Commission FP6 STRP grant number 018947 (LSHG-CT-2006-01947) and also received funding from the European Community's Seventh Framework Programme (FP7/2007-2013)/grant agreement HEALTH-F4-2007-201413 by the European Commission under the program “Quality of Life and Management of the Living Resources” of 5th Framework Programme (no. QLG2-CT-2002-01254). High-throughput analysis of the ERF data was supported by joint grant from Netherlands Organization for Scientific Research and the Russian Foundation for Basic Research (NWO-RFBR 047.017.043).

The INGI research was supported by funds from Compagnia di San Paolo, Torino, Italy; Fondazione Cariplo, Italy and Ministry of Health, Ricerca Finalizzata 2008 and CCM 2010 and Telethon, Italy. Additional support was provided by the Italian Ministry of Health (RF 2010 to PG), FVG Region, and Fondo Trieste.

The NTR study was supported by multiple grants from the Netherlands Organization for Scientific Research (NWO: 016-115-035, 463-06-001, 451-04-034), ZonMW (31160008, 911-09-032); from the Institute for Health and Care Research (EMGO + ); and from the Biomolecular Resources Research Infrastructure (BBMRI-NL, 184.021.007), European Research Council (ERC-230374). Genotyping was made possible by grants from NWO/SPI 56-464-14192, Genetic Association Information Network (GAIN) of the Foundation for the National Institutes of Health, Rutgers University Cell and DNA Repository (NIMH U24 MH068457-06), the Avera Institute, Sioux Falls (USA), and the National Institutes of Health (NIH R01 HD042157-01A1, MH081802, Grand Opportunity grants 1RC2 MH089951 and 1RC2 MH089995). B.D.L. is supported by a PhD grant (201206180099) from the China Scholarship Council.

QIMR funding was provided by the Australian National Health and Medical Research Council (241944, 339462, 389927, 389875, 389891, 389892, 389938, 442915, 442981, 496739, 552485, 552498), the Australian Research Council (A7960034, A79906588, A79801419, DP0770096, DP0212016, DP0343921), the FP-5 GenomEUtwin Project (QLG2-CT-2002-01254), and the US National Institutes of Health (NIH grants AA07535, AA10248, AA13320, AA13321, AA13326, AA14041, MH66206). Statistical analyses were carried out on the Genetic Cluster Computer, which is financially supported by the Netherlands Scientific Organization (NWO 480-05-003). S.E.M. and D.L.D. are supported by the National Health and Medical Research Council (NHMRC) Fellowship Scheme.

The 20-year follow-up of Generation 2 of the Western Australian Pregnancy Cohort (Raine) Study was funded by Australian National Health and Medical Research Council (NHMRC) project grant 1021105, Lions Eye Institute, the Australian Foundation for the Prevention of Blindness, and the Ophthalmic Research Institute of Australia. S.Y. is supported by NHMRC Early Career Fellowship (CJ Martin - Overseas Biomedical Fellowship).

The Rotterdam Study is supported by the Netherlands Organization of Scientific Research NWO Investments (nr. 175.010.2005.011, 911-03-012). This study is funded by the Research Institute for Diseases in the Elderly (014-93-015; RIDE2), the Netherlands Genomics Initiative (NGI)/Netherlands Organization for Scientific Research (NWO) project nr. 050-060-810. The Rotterdam Study is supported by the Erasmus MC and Erasmus University Rotterdam; the Netherlands Organization for Scientific Research (NWO); the Netherlands Organization for Health Research and Development (ZonMw); the Research Institute for Diseases in the Elderly (RIDE) the Netherlands Genomics Initiative (NGI); the Ministry of Education, Culture and Science; the Ministry of Health Welfare and Sport; the European Commission (DG XII); and the Municipality of Rotterdam. The generation and management of GWAS genotype data for the Rotterdam Study were executed by the Human Genotyping Facility of the Genetic Laboratory of the Department of Internal Medicine, Erasmus MC. F.L. is supported by a Chinese recruiting program, the National Thousand Young Talents Award, and by the National Natural Science Foundation of China (NSFC) (91651507).

The TwinsUK study was funded by the Wellcome Trust (105022/Z/14/Z); European Community's Seventh Framework Programme (FP7/2007-2013). The study also receives support from the National Institute for Health Research (NIHR)-funded BioResource, Clinical Research Facility and Biomedical Research Centre based at Guy's and St Thomas’ NHS Foundation Trust in partnership with King's College London. SNP genotyping was performed by the Wellcome Trust Sanger Institute and National Eye Institute via NIH/CIDR.