Nature's randomised trials

A randomised trial without an intervention is difficult to envisage. In today's Lancet, however, Nic Timpson and colleagues 1 Timpson NJ Lawler DA Harbord RM et al. C-reactive protein and its role in metabolic syndrome: mendelian randomisation study. Lancet. 2005; 366: 1954-1959 Summary Full Text Full Text PDF PubMed Scopus (274) Google Scholar take advantage of natural genetic randomisation during sexual reproduction—that of alleles bearing single nucleotide polymorphisms (SNPs) governing the abundance of C-reactive protein (CRP)—to assess whether associations between CRP and components of the metabolic syndrome are causal. C-reactive protein and its role in metabolic syndrome: mendelian randomisation studyDisparity between estimates of the association between plasma CRP and phenotypes comprising the metabolic syndrome derived from conventional analyses and those from a mendelian randomisation approach suggests that there is no causal association between CRP and the metabolic syndrome phenotypes. Full-Text PDF