01615nas a2200253   4500000000100000008004100001260004500042653002000087653001200107653001600119100001100135700001400146700001300160700001000173700001300183700001100196700001000207245011700217300001200334490000800346050001500354520097800369022001401347       2012                            d  c05/2012bOxford University PressaOxford10aType 2 reaction10aleprosy10aInterleukin1 aCosta 1 aMartelli 1 aStefani 1 aMira 1 aSampaio 1 aSousa 1 aFava 00aGenetic and Immunological Evidence Implicates Interleukin 6 as a Susceptibility Gene for Leprosy Type 2 Reaction  a1417-240 v205  aSOUSA 20123 aIn leprosy, type 1 reaction (T1R) and type 2 reaction (T2R) are major causes of nerve injury and permanent disabilities. A previous study on plasma levels of 27 cytokines in patients with T1R or T2R and controls with nonreactional leprosy identified the gene for interleukin 6 (IL-6) as a candidate for genetic analysis. Two nested case-control studies were built from a cohort of 409 patients with leprosy from central Brazil, monitored for T1R and T2R. There was evidence for association between T2R and IL-6 tag single-nucleotide polymorphisms rs2069832 (P = .002), rs2069840 (P = .03), and rs2069845 (P = .04), with information on the entire IL-6 locus, as well as functional IL-6 variant rs1800795 (P = .005). Moreover, IL-6 plasma levels in patients with T2R correlated with IL-6 genotypes (P = .04). No association was found between IL-6 variants and T1R. Identifying genetic predictive factors for leprosy reactions may have a major impact on preventive strategies.  a1537-6613