| 1 | Eur. Psychiatry 2004 Sep 19: 354-7 |
|---|---|
| PMID | 15363474 |
| Title | The CLDN5 locus may be involved in the vulnerability to schizophrenia. |
| Abstract | The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3'-untranslated region of the CLDN5 locus was associated with schizophrenia (chi(2) = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5'-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (chi(2)) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (chi(2) = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 2 | Prostaglandins Leukot. Essent. Fatty Acids 2005 Dec 73: 441-5 |
| PMID | 16181776 |
| Title | A study of the combined effect of the CLDN5 locus and the genes for the phospholipid metabolism pathway in schizophrenia. |
| Abstract | The present study attempts to test the combined effect of the CLDN5 gene and those for the phospholipid metabolism pathway, including PTGS1, PTGS2, PLA2G4A and PLA2G4C. We detected five single nucleotide polymorphisms (SNPs) present in these genes among 131 British family trios of schizophrenic patients. The transmission disequilibrium test (TDT) showed that BanI-SNP located in the 5'-flanking region of the PLA2G4A gene was associated with schizophrenia (chi(2) = 5.16, P = 0.023) although the others failed to show such allelic associations. The global P-value was 0.150 for 1000 permutations with the TDT analysis. The conditioning on genotype test, but not on allele test, revealed a strong association for the combination of the CLDN5 gene with the PLA2G4A gene (chi(2) = 10.17, df = 2, P = 0.006). The present results suggest that the PLA2G4A locus may be involved in schizophrenia and its combination with the CLDN5 gene may increase further the risk for the illness. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 3 | Prostaglandins Leukot. Essent. Fatty Acids 2005 Dec 73: 441-5 |
| PMID | 16181776 |
| Title | A study of the combined effect of the CLDN5 locus and the genes for the phospholipid metabolism pathway in schizophrenia. |
| Abstract | The present study attempts to test the combined effect of the CLDN5 gene and those for the phospholipid metabolism pathway, including PTGS1, PTGS2, PLA2G4A and PLA2G4C. We detected five single nucleotide polymorphisms (SNPs) present in these genes among 131 British family trios of schizophrenic patients. The transmission disequilibrium test (TDT) showed that BanI-SNP located in the 5'-flanking region of the PLA2G4A gene was associated with schizophrenia (chi(2) = 5.16, P = 0.023) although the others failed to show such allelic associations. The global P-value was 0.150 for 1000 permutations with the TDT analysis. The conditioning on genotype test, but not on allele test, revealed a strong association for the combination of the CLDN5 gene with the PLA2G4A gene (chi(2) = 10.17, df = 2, P = 0.006). The present results suggest that the PLA2G4A locus may be involved in schizophrenia and its combination with the CLDN5 gene may increase further the risk for the illness. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 4 | Schizophr. Res. 2005 Jun 75: 139-41 |
| PMID | 15820333 |
| Title | Further study of a genetic association between the CLDN5 locus and schizophrenia. |
| Abstract | -1 |
| SCZ Keywords | schizophrenia, schizophrenic |
| 5 | Med. Hypotheses 2005 -1 64: 547-52 |
| PMID | 15617864 |
| Title | Gene, gut and schizophrenia: the meeting point for the gene-environment interaction in developing schizophrenia. |
| Abstract | Both schizophrenia and celiac disease involve a genetic component. Several lines of evidence have shown a genetic relationship between these two conditions. Celiac disease is characterized by damage to the microscopic finger-like projections called villi, which line the small intestine and play a significant role in digestion, due to an inflammatory condition caused by a reaction to wheat gluten or related rye and barley proteins. Celiac disease represents not only malabsorption leading to a poor nutritional condition but also an alteration of gut permeability. Individuals with a history of a childhood celiac condition have a raised risk of developing schizophrenia. Psychotic symptoms often occur in adult celiac disease. It can be hypothesized that apart from malnutrition, the meeting point for the gene-environment interaction may be an alteration in gut permeability, in which the gut may lose its capacity to block exogenous psychosis-causing substances that may enter the body thus causing the development of schizophrenia and other mental conditions. To support this hypothesis, the conditional test was conducted to look at the combined effect of the CLDN5 gene involved in forming permeability barriers and the DQB1 gene that has been found to be associated with celiac disease. The results demonstrate that these two genes possibly work together in conferring a susceptibility to schizophrenia. |
| SCZ Keywords | schizophrenia, schizophrenic |
| 6 | Psychiatr. Genet. 2008 Oct 18: 255-6 |
| PMID | 18797402 |
| Title | Replication study for associations between polymorphisms in the CLDN5 and DGCR2 genes in the 22q11 deletion syndrome region and schizophrenia. |
| Abstract | -1 |
| SCZ Keywords | schizophrenia, schizophrenic |
| 7 | Psychiatry Res 2010 Jun 178: 223 |
| PMID | 20452046 |
| Title | A weak association of the CLDN5 locus with schizophrenia in Chinese case-control samples. |
| Abstract | -1 |
| SCZ Keywords | schizophrenia, schizophrenic |
| 8 | Iran. J. Public Health 2014 Jan 43: 79-83 |
| PMID | 26060683 |
| Title | Polymorphism of the CLDN5 gene and Schizophrenia in an Iranian Population. |
| Abstract | The gene coding claudin (CLDN5) is located on 22q11. Since the proteins of CLDN5 family are a ma-jor component for barrier-forming tight junctions, it may be important to test whether or not the CLDN5 locus could be associated with schizophrenia. A total of 150 individuals affected with schizophrenia and 150 healthy persons were recruited. The relation-ship between the three single nucleotide polymorphism (SNPs) and schizophrenia disease was studied using polymer-ase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) technique. The PCR products were completely digested with restriction enzymes of DpnII, PvuII and BstNI, and then separated on agarose gel. The statis-tical investigations and haplotype analysis were also performed. The transmission disequilibrium test (TDT) exhibited weak association between rs10314 [C/G] and schizo-phrenia (v2 = 3.55, P = 0.022), but the other two SNPs did not show such an association. The global chi-square test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (v2 = 6.33, P = 0.025). The v2 test for LD between SNPs indicated that these three SNPs were in strong LD. Collectively, LD analysis showed that the CLDN5 locus was associated with schizophrenia in an Iranian population. |
| SCZ Keywords | schizophrenia, schizophrenic |