BACKGROUND: Bipolar disorder (BD) is considered as a multifactorial disorder involving complex interactions between genetic and environmental factors, where immune dysfunction is thought to play a key etiopathogenic role. In particular, excess of winter births associated with early-life infections raise the possibility of the implication of innate immunity. Given the pivotal role of Toll-like receptor 4 (TLR-4), a major innate immune sensor molecule, we hypothesized that genetic variations of TLR-4 may be associated to BD. METHODS: Genomic DNAs from 572 BD patients and 202 healthy controls (HC) were analyzed for the distribution of six single nucleotides polymorphisms (SNPs) scattered along the TLR-4 locus (rs1927914, rs10759932, rs4986790, rs4986791, rs11536889 and rs11536891). Associations between BD and these polymorphisms were examined using the Chi-square test. RESULTS: We found that rs1927914 AA and rs11536891 TT genotype are more frequent in BD patients than in controls (corrected p; pc=.02 and .02 respectively) particularly in early-onset BD patients (pc=.004 and .006) born during the summer season (pc=.02 and .002 respectively). We also found that rs4986790 AG and rs4986791 CT genotypes were significantly associated with presence of autoimmune thyroiditis (pc=.002). LIMITATIONS: Our results are to be confirmed by replication in independent BD cohorts. CONCLUSIONS: We report for the first time a genetic association between BD and TLR-4 a major player of innate immunity. Possible mechanisms underlying bipolar disorders linking altered TLR-4 expression and increased susceptibility to infections and/or autoimmunity are discussed.
BACKGROUND:Bipolar disorder (BD) is considered as a multifactorial disorder involving complex interactions between genetic and environmental factors, where immune dysfunction is thought to play a key etiopathogenic role. In particular, excess of winter births associated with early-life infections raise the possibility of the implication of innate immunity. Given the pivotal role of Toll-like receptor 4 (TLR-4), a major innate immune sensor molecule, we hypothesized that genetic variations of TLR-4 may be associated to BD. METHODS: Genomic DNAs from 572 BDpatients and 202 healthy controls (HC) were analyzed for the distribution of six single nucleotides polymorphisms (SNPs) scattered along the TLR-4 locus (rs1927914, rs10759932, rs4986790, rs4986791, rs11536889 and rs11536891). Associations between BD and these polymorphisms were examined using the Chi-square test. RESULTS: We found that rs1927914 AA and rs11536891 TT genotype are more frequent in BDpatients than in controls (corrected p; pc=.02 and .02 respectively) particularly in early-onset BDpatients (pc=.004 and .006) born during the summer season (pc=.02 and .002 respectively). We also found that rs4986790 AG and rs4986791 CT genotypes were significantly associated with presence of autoimmune thyroiditis (pc=.002). LIMITATIONS: Our results are to be confirmed by replication in independent BD cohorts. CONCLUSIONS: We report for the first time a genetic association between BD and TLR-4 a major player of innate immunity. Possible mechanisms underlying bipolar disorders linking altered TLR-4 expression and increased susceptibility to infections and/or autoimmunity are discussed.
Authors: Seva G Khambadkone; Zachary A Cordner; Faith Dickerson; Emily G Severance; Emese Prandovszky; Mikhail Pletnikov; Jianchun Xiao; Ye Li; Gretha J Boersma; C Conover Talbot; Wayne W Campbell; Christian S Wright; C Evan Siple; Timothy H Moran; Kellie L Tamashiro; Robert H Yolken Journal: Mol Psychiatry Date: 2018-07-18 Impact factor: 15.992
Authors: Borja García-Bueno; Patricia Gassó; Karina S MacDowell; Luis F Callado; Sergi Mas; Miguel Bernardo; Amalia Lafuente; J Javier Meana; Juan C Leza Journal: J Psychiatry Neurosci Date: 2016-04 Impact factor: 6.186