Genome-wide association study of circulating interleukin 6 levels identifies novel loci

Ahluwalia, Tarunveer S; Prins, Bram P; Abdollahi, Mohammadreza; Armstrong, Nicola J; Aslibekyan, Stella; Bain, Lisa; Jefferis, Barbara; Baumert, Jens; Beekman, Marian; Ben-Shlomo, Yoav; Bis, Joshua C; Mitchell, Braxton D; de Geus, Eco; Delgado, Graciela E; Marek, Diana; Eriksson, Joel; Kajantie, Eero; Kanoni, Stavroula; Kemp, John P; Lu, Chen; Marioni, Riccardo E; McLachlan, Stela; Milaneschi, Yuri; Nolte, Ilja M; Petrelis, Alexandros M; Porcu, Eleonora; Sabater-Lleal, Maria; Naderi, Elnaz; Seppälä, Ilkka; Shah, Tina; Singhal, Gaurav; Standl, Marie; Teumer, Alexander; Thalamuthu, Anbupalam; Thiering, Elisabeth; Trompet, Stella; Ballantyne, Christie M; Benjamin, Emelia J; Casas, Juan P; Toben, Catherine; Dedoussis, George; Deelen, Joris; Durda, Peter; Engmann, Jorgen; Feitosa, Mary F; Grallert, Harald; Hammarstedt, Ann; Harris, Sarah E; Homuth, Georg; Hottenga, Jouke-Jan; Jalkanen, Sirpa; Jamshidi, Yalda; Jawahar, Magdalene C; Jess, Tine; Kivimaki, Mika; Kleber, Marcus E; Lahti, Jari; Liu, Yongmei; Marques-Vidal, Pedro; Mellström, Dan; Mooijaart, Simon P; Müller-Nurasyid, Martina; Penninx, Brenda; Revez, Joana A; Rossing, Peter; Räikkönen, Katri; Sattar, Naveed; Scharnagl, Hubert; Sennblad, Bengt; Silveira, Angela; Pourcain, Beate St; Timpson, Nicholas J; Trollor, Julian; van Dongen, Jenny; Van Heemst, Diana; Visvikis-Siest, Sophie; Vollenweider, Peter; Völker, Uwe; Waldenberger, Melanie; Willemsen, Gonneke; Zabaneh, Delilah; Morris, Richard W; Arnett, Donna K; Baune, Bernhard T; Boomsma, Dorret I; Chang, Yen-Pei C; Deary, Ian J; Deloukas, Panos; Eriksson, Johan G; Evans, David M; Ferreira, Manuel A; Gaunt, Tom; Gudnason, Vilmundur; Hamsten, Anders; Heinrich, Joachim; Hingorani, Aroon; Humphries, Steve E; Jukema, J Wouter; Koenig, Wolfgang; Kumari, Meena; Kutalik, Zoltan; Lawlor, Deborah A; Lehtimäki, Terho; März, Winfried; Mather, Karen A; Naitza, Silvia; Nauck, Matthias; Ohlsson, Claes; Price, Jackie F; Raitakari, Olli; Rice, Ken; Sachdev, Perminder S; Slagboom, Eline; Sørensen, Thorkild I A; Spector, Tim; Stacey, David; Stathopoulou, Maria G; Tanaka, Toshiko; Wannamethee, S Goya; Whincup, Peter; Rotter, Jerome I; Dehghan, Abbas; Boerwinkle, Eric; Psaty, Bruce M; Snieder, Harold; Alizadeh, Behrooz Z

Interleukin 6 (IL-6) is a multifunctional cytokine with both pro- and anti-inflammatory properties with a heritability estimate of up to 61%. The circulating levels of IL-6 in blood have been associated with an increased risk of complex disease pathogenesis. We conducted a two-staged, discovery and replication meta genome-wide association study (GWAS) of circulating serum IL-6 levels comprising up to 67 428 (n(discovery) = 52 654 and n(replication) = 14 774) individuals of European ancestry. The inverse variance fixed effects based discovery meta-analysis, followed by replication led to the identification of two independent loci, IL1F10/IL1RN rs6734238 on chromosome (Chr) 2q14, (P(combined) = 1.8 × 10(−11)), HLA-DRB1/DRB5 rs660895 on Chr6p21 (P(combined) = 1.5 × 10(−10)) in the combined meta-analyses of all samples. We also replicated the IL6R rs4537545 locus on Chr1q21 (P(combined) = 1.2 × 10(−122)). Our study identifies novel loci for circulating IL-6 levels uncovering new immunological and inflammatory pathways that may influence IL-6 pathobiology.