Figure 3.
Graphical representation of the reciprocal Mendelian randomization framework used in main analyses.
Dotted line represents the unknown direction of relationship between circulating CRP and BMI.
Relationships (i) and (ii) denote the informative associations between CRP genotypes, FTO genotypes and circulating CRP and body mass index.
Single-headed arrows represent the known (and assumed causal and largely non-confounded) relationships between variation at the CRP and FTO loci and circulating CRP and body mass index respectively.