Liu Y.-L.CHIH-MIN LIUFann C.S.-J.Yang W.C.Chen Y.-H.Tseng L.-J.Liu S.-K.MING-HSIEN HSIEHTZUNG-JENG HWANGChan H.-Y.Chen J.-J.WEI J. CHENHAI-GWO HWU2020-03-172020-03-172010-01-14https://scholars.lib.ntu.edu.tw/handle/123456789/476425The pathophysiological process of schizophrenia is still unclear. The levels of interleukine-6 (IL-6) and its receptor, soluble IL-6R, have been reported to be elevated in the plasma and cerebrospinal fluid of schizophrenic patients. In this study, we tested the association of genetic variants of IL-6 and IL-6R with schizophrenia. Genotyping of three single nucleotide polymorphisms (SNP) for each IL-6 (IL-6-1, IL-6-2, and IL-6-3) and IL-6R (rs4845617 = IL-6R1, rs4553185 = IL-6R2, and rs4379670 = IL-6R3) gene was performed in 100 patients with schizophrenia and 113 normal controls. The polymorphisms of IL-6R2 were genotyped using Tetra-primer ARMS PCR. IL-6R3 polymorphisms were genotyped using restriction fragment length polymorphism (RFLP) with Apo I enzyme as the restriction enzyme. All other polymorphisms were genotyped using the direct sequencing method. We found a di-nucleotide haplotype block and a tri-nucleotide haplotype block in the genes of IL-6 and IL-6R, respectively. All six SNPs and their haplotypes failed to show a significant association with schizophrenia. The IL-6-2 SNP showed a nominally significant association with the positive symptoms of schizophrenia (p = 0.0472). We conclude that the genetic variants of IL-6 and IL-6R are not associated with schizophrenia. In order to verify this result, further study using a larger sample size and exploring the association between the genotype of IL-6-2 and plasma level of IL-6 is recommended. ? 2009 Elsevier Ireland Ltd. All rights reserved.[SDGs]SDG3dinucleotide; interleukin 6; interleukin 6 receptor; trinucleotide; 3' untranslated region; adult; article; controlled study; disease predisposition; disease severity; enzyme regulation; exon; female; gene frequency; gene locus; genetic association; genetic marker; genetic variability; genotype; human; intron; major clinical study; male; negative syndrome; phenotype; positive syndrome; priority journal; promoter region; restriction fragment length polymorphism; schizophrenia; single nucleotide polymorphism; Taiwan; Adult; Asian Continental Ancestry Group; Female; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Interleukin-6; Male; Polymorphism, Single Nucleotide; Receptors, Interleukin-6; Schizophrenia; Taiwanjournal article10.1016/j.neulet.2009.11.026199143342-s2.0-72249102808