rs3024490

According to a 2010 report, each A (minor) allele at rs3024490 in the IL10 gene increased the risk of Behçet's disease about 1.4 times in a Turkish population. The aim of the study was to map SNP/gene associations with environmental pathogen-richness in relation to genomic variations across geographic human populations. This 2009 article found that "six risk alleles for inflammatory bowel (IBD) or celiac disease are significantly correlated with micropathogen richness. These data support the hygiene hypothesis for IBD and provide a large set of putative targets for susceptibility to helminth infections." (Abstract) Table I. identified rs3024490 among a list of 44 SNPs analyzed in relation to micro- and macro-pathogens. This SNP was not previously associated with IBD and celiac disease and was negatively associated with pathogen richness. This 2009 study identified a haplotype among Ghanaians consisting of minor alleles at four SNPs in the IL-10 gene: rs1800871, rs1800872, rs3024490 and rs1554286. This combination of risk alleles led to lower IL-10 expression and higher TNF gene expression, resulting in a pro-inflammatory response. The authors explain that in Ghana, "pro-inflammatory alleles rescue their carriers of excess mortality in adverse environmental conditions" such as drinking from boreholes, and thus minor alleles occur more frequently in African populations, but "in an affluent environment, the same pro-inflammatory response leads to increased mortality," and minor alleles occur much less frequently (i.e. in Caucasian populations).