title: Genetic polymorphism of IL-12 p40 gene in immune-mediated disease.
abstract: Understanding of the genetic basis of autoimmune diseases is currently incomplete. Cytokine gene polymorphisms warrant consideration as factors explaining variation in the human immune and inflammatory responses and as candidate susceptibility genes for related pathological states. Interleukin 12 (IL-12) is a key regulator of the polarisation of immune responses to T helper 1 or 2 categories and plays a role in autoimmune and infectious diseases. Using a bioinformatic strategy, we aligned cDNA and expressed sequence tag sequences to identify putative polymorphic regions of the IL-12 p40 gene. Position 1188 in the 3' untranslated region (UTR) was polymorphic with the frequency of the common allele around 80% in healthy UK Caucasoids. PCR genotyping of multiple Caucasoid groups and an African group showed significant population variation. In a case-control design, the polymorphism was not associated with rheumatoid arthritis, Felty's syndrome or large granular lymphocyte syndrome with arthritis or multiple sclerosis. A nonsignificant increase in the B allele frequency was observed in the rare large granular lymphocyte syndrome without arthritis (odds ratio 2.02 95% CI 0.95-4.3). This new genetic marker could be useful in anthropological studies and should be investigated in other autoimmune, allergic, inflammatory and infectious diseases.
authors.affiliation: Department of Rheumatology, Division of Medicine, 5th Floor Thomas Guy House, Guy's, King's and St Thomas' Hospitals School of Medicine, King's College, Guy's Hospital Campus, London SE1 9RT, UK. mhall@hgmp.mrc.ac.uk
authors.forename: M A
authors.initials: MA
authors.lastname: Hall
authors.forename: E
authors.initials: E
authors.lastname: McGlinn
authors.forename: G
authors.initials: G
authors.lastname: Coakley
authors.forename: S A
authors.initials: SA
authors.lastname: Fisher
authors.forename: K
authors.initials: K
authors.lastname: Boki
authors.forename: D
authors.initials: D
authors.lastname: Middleton
authors.forename: E
authors.initials: E
authors.lastname: Kaklamani
authors.forename: H
authors.initials: H
authors.lastname: Moutsopoulos
authors.forename: T P
authors.initials: TP
authors.lastname: Loughran
authors.forename: W E
authors.initials: WE
authors.lastname: Ollier
authors.forename: G S
authors.initials: GS
authors.lastname: Panayi
authors.forename: J S
authors.initials: JS
authors.lastname: Lanchbury
mesh_terms: D000483:Alleles; D000818:Animals; D001172:Arthritis, Rheumatoid / Q000235:genetics / Q000276:immunology; D001483:Base Sequence; D016022:Case-Control Studies; D017931:DNA Primers / Q000235:genetics; D005258:Felty Syndrome / Q000235:genetics / Q000276:immunology; D005787:Gene Frequency; D014644:Genetic Variation; D006115:Greece; D006801:Humans; D007154:Immune System Diseases / Q000235:genetics* / Q000276:immunology*; D018664:Interleukin-12 / Q000235:genetics*; D008218:Lymphocytosis / Q000235:genetics / Q000276:immunology; D009103:Multiple Sclerosis / Q000235:genetics / Q000276:immunology; D002679:Pan troglodytes; D011110:Polymorphism, Genetic; D013577:Syndrome; D006113:United Kingdom
chemical_list: D017931:DNA Primers; D018664:Interleukin-12