Heritability of variation in glycaemic response to metformin: a genome-wide complex trait analysis

Kaixin Zhou (Lead / Corresponding author), Louise Donnelly, Jian Yang, Miaoxin Li, Harshal Deshmukh, Natalie Van Zuydam, Emma Ahlqvist, Chris C. Spencer, Lief Groop, Andrew D. Morris, Helen M. Colhoun, Pak C. Sham, Mark I. McCarthy, Colin N.A. Palmer, Ewan R. Pearson

    Research output: Contribution to journalArticlepeer-review

    103 Citations (Scopus)
    189 Downloads (Pure)


    Background: Metformin is a first-line oral agent used in the treatment of type 2 diabetes, but glycaemic response to this drug is highly variable. Understanding the genetic contribution to metformin response might increase the possibility of personalising metformin treatment. We aimed to establish the heritability of glycaemic response to metformin using the genome-wide complex trait analysis (GCTA) method. Methods: In this GCTA study, we obtained data about HbA 1cconcentrations before and during metformin treatment from patients in the Genetics of Diabetes Audit and Research in Tayside Scotland (GoDARTS) study, which includes a cohort of patients with type 2 diabetes and is linked to comprehensive clinical databases and genome-wide association study data. We applied the GCTA method to estimate heritability for four definitions of glycaemic response to metformin: absolute reduction in HbA1c; proportional reduction in HbA1c; adjusted reduction in HbA1c; and whether or not the target on-treatment HbA1c of less than 7% (53 mmol/mol) was achieved, with adjustment for baseline HbA1c and known clinical covariates. Chromosome-wise heritability estimation was used to obtain further information about the genetic architecture. Findings: 5386 individuals were included in the final dataset, of whom 2085 had enough clinical data to define glycaemic response to metformin. The heritability of glycaemic response to metformin varied by response phenotype, with a heritability of 34% (95% CI 1-68; p=0·022) for the absolute reduction in HbA1c, adjusted for pretreatment HbA1c. Chromosome-wise heritability estimates suggest that the genetic contribution is probably from individual variants scattered across the genome, which each have a small to moderate effect, rather than from a few loci that each have a large effect. Interpretation: Glycaemic response to metformin is heritable, thus glycaemic response to metformin is, in part, intrinsic to individual biological variation. Further genetic analysis might enable us to make better predictions for stratified medicine and to unravel new mechanisms of metformin action.

    Original languageEnglish
    Pages (from-to)481-487
    Number of pages7
    JournalThe Lancet: Diabetes and Endocrinology
    Issue number6
    Publication statusPublished - Jun 2014


    Dive into the research topics of 'Heritability of variation in glycaemic response to metformin: a genome-wide complex trait analysis'. Together they form a unique fingerprint.

    Cite this