Supplementary Material for: <i>DTNBP1, NRG1, DAOA</i>, <i>DAO</i> and <i>GRM3</i> Polymorphisms and Schizophrenia: An Association Study

<i>Background:</i> Several studies of the dystrobrevin-binding protein 1 gene <i>(DTNBP1)</i>, neuregulin 1 <i>(NRG1)</i>, <i>D</i>-amino-acid oxidase <i>(DAO)</i>, <i>DAO</i> activator <i>(DAOA, G72)</i>, and metabotropic glutamate receptor 3 <i>(GRM3)</i> genes have suggested an association between variants of these genes and schizophrenia. <i>Methods:</i> In a replication attempt, single-nucleotide polymorphisms of the <i>DTNBP1, NRG1, DAO, DAOA, </i>and<i> GRM3 </i>genes were analyzed in three independent Scandinavian schizophrenia case-control samples. <i>Results:</i> One <i>DTNBP1 </i>and three <i>GRM3</i> single-nucleotide polymorphisms showed nominal significant associations to the disease. However, after correction for multiple testing, there were no statistically significant allele, genotype or haplotype case-control differences. <i>Conclusions:</i> The present Scandinavian results do not verify previous associations between the analyzed <i>DTNBP1, NRG1, DAO, DAOA, </i>and<i> GRM3 </i>gene polymorphisms and schizophrenia. Additional studies and meta-analyses are warranted to shed further light on these relationships.

<i>背景：</i> 多项针对肌营养不良蛋白结合蛋白1基因（DTNBP1）、神经调节蛋白1（NRG1）、D-氨基酸氧化酶（DAO）、DAO激活因子（DAOA, G72）以及代谢型谷氨酸受体3（GRM3）的研究均表明，上述基因的变异与精神分裂症存在关联。<i>方法：</i> 为开展重复验证研究，本研究在三个独立的斯堪的纳维亚精神分裂症病例-对照样本中，对DTNBP1、NRG1、DAO、DAOA及GRM3基因的单核苷酸多态性（single-nucleotide polymorphisms）进行了分析。<i>结果：</i> 1个DTNBP1基因的单核苷酸多态性位点与3个GRM3基因的单核苷酸多态性位点呈现出名义上的显著疾病关联。但经多重检验校正后，等位基因、基因型或单体型的病例-对照组间差异均无统计学意义。<i>结论：</i> 本次斯堪的纳维亚地区的研究结果未能证实此前报道的DTNBP1、NRG1、DAO、DAOA及GRM3基因多态性与精神分裂症的关联。后续需开展更多研究及荟萃分析，以进一步阐明此类基因与精神分裂症的潜在关系。