title: Association study of interleukin-4 polymorphisms with paranoid schizophrenia in the Polish population: a critical approach.
abstract: Changes in immunological system are one of dysfunctions reported in schizophrenia. Some changes based on an imbalance between Th1 and Th2 cytokines results from cytokine gene polymorphisms. Interleukin-4 gene (IL4) is considered as a potential candidate gene in schizophrenia association studies. The aim of the current case-control study was to examine whether the -590C/T (rs2243250) and -33C/T (rs2070874) IL4 gene polymorphisms are implicated in paranoid schizophrenia development in the Polish population. Genotyping of polymorphisms was performed by using PCR-RFLP technique. The genotypes and alleles distribution of both SNPs were analysed in patients (n = 182) and healthy individuals constituted the control group (n = 215). The connection between some clinical variables and studied polymorphisms has been examined as well. We did not revealed any association between the -590C/T and -33C/T polymorphisms and paranoid schizophrenia. In case of both SNPs the homozygous TT genotype was extremely rare. Both polymorphic sites of the IL4 gene were found to be in a very strong linkage disequilibrium. However we did not identify a haplotype predispose to paranoid schizophrenia. No associations were also observed between the clinical course and psychopathology of the disease and the genotypes of both analysed polymorphisms. Our results suggest that the polymorphisms -590C/T in IL4 gene promoter region and -33C/T in the 5'-UTR are not involved in the pathophysiology of paranoid schizophrenia in Polish residents.
authors.affiliation: Department of Medical Genetics, Medical University of Silesia, Ostrogorska 30, 41-200 Sosnowiec, Poland. afila@sum.edu.pl
authors.forename: Anna
authors.initials: A
authors.lastname: Fila-Danilow
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Kucia
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Kowalczyk
authors.forename: Aleksander
authors.initials: A
authors.lastname: Owczarek
authors.forename: Monika
authors.initials: M
authors.lastname: Paul-Samojedny
authors.forename: Paulina
authors.initials: P
authors.lastname: Borkowska
authors.forename: Renata
authors.initials: R
authors.lastname: Suchanek
authors.forename: Jan
authors.initials: J
authors.lastname: Kowalski
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D000704:Analysis of Variance; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D015847:Interleukin-4 / Q000235:genetics*; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D011044:Poland; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D012563:Schizophrenia, Paranoid / Q000235:genetics*; D044465:White People / Q000235:genetics*; D055815:Young Adult
chemical_list: D015847:Interleukin-4