Rxivist logo

Efficient Bayesian mixed model analysis increases association power in large cohorts

By Po-Ru Loh, George Tucker, Brendan K. Bulik-Sullivan, Bjarni J. Vilhjálmsson, Hilary K Finucane, Daniel I Chasman, Paul M Ridker, Benjamin M Neale, Bonnie Berger, Nick Patterson, Alkes Price

Posted 09 Aug 2014
bioRxiv DOI: 10.1101/007799 (published DOI: 10.1038/ng.3190)

Linear mixed models are a powerful statistical tool for identifying genetic associations and avoiding confounding. However, existing methods are computationally intractable in large cohorts, and may not optimize power. All existing methods require time cost O(MN^2) (where N = #samples and M = #SNPs) and implicitly assume an infinitesimal genetic architecture in which effect sizes are normally distributed, which can limit power. Here, we present a far more efficient mixed model association method, BOLT-LMM, which requires only a small number of O(MN) iterations and increases power by modeling more realistic, non-infinitesimal genetic architectures via a Bayesian mixture prior on marker effect sizes. We applied BOLT-LMM to nine quantitative traits in 23,294 samples from the Women's Genome Health Study (WGHS) and observed significant increases in power, consistent with simulations. Theory and simulations show that the boost in power increases with cohort size, making BOLT-LMM appealing for GWAS in large cohorts.

Download data

  • Downloaded 2,351 times
  • Download rankings, all-time:
    • Site-wide: 8,190
    • In genetics: 340
  • Year to date:
    • Site-wide: 48,693
  • Since beginning of last month:
    • Site-wide: 36,392

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide