Hujoel IA, et al. - A Mendelian randomization was used to explore whether genetically determined copper and zinc levels play a causal role in the development of irritable bowel syndrome (IBS). Researchers used three single-nucleotide polymorphisms (SNPs) (rs1175550, rs2769264, and rs2769270) associated with erythrocyte copper levels, and 3 SNPs associated with erythrocyte zinc levels (rs11638477, rs1532423, and rs2120019) in the Australian Twin Study (1993-1996 and 2001-2005) as instrumental variables for levels of these metals. They evaluated the relationship of these SNPs with IBS using summary statistics computed on 340,331 individuals from the UK Biobank, 5,548 of whom had IBS (2006-2010). The findings illustrate that high erythrocyte copper levels may be protective against IBS development. In high-risk individuals, targeting higher levels may thus provide an avenue to reduce the likelihood of IBS development.