title: A sex-specific association of common variants of neuroligin genes (NLGN3 and NLGN4X) with autism spectrum disorders in a Chinese Han cohort.
abstract: BACKGROUND
  Synaptic genes, NLGN3 and NLGN4X, two homologous members of the neuroligin family, have been supposed as predisposition loci for autism spectrum disorders (ASDs), and defects of these two genes have been identified in a small fraction of individuals with ASDs. But no such rare variant in these two genes has as yet been adequately replicated in Chinese population and no common variant has been further investigated to be associated with ASDs.
  
  
  METHODS
  7 known ASDs-related rare variants in NLGN3 and NLGN4X genes were screened for replication of the initial findings and 12 intronic tagging single nucleotide polymorphisms (SNPs) were genotyped for case-control association analysis in a total of 229 ASDs cases and 184 control individuals in a Chinese Han cohort, using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry.
  
  
  RESULTS
  We found that a common intronic variant, SNP rs4844285 in NLGN3 gene, and a specific 3-marker haplotype XA-XG-XT (rs11795613-rs4844285-rs4844286) containing this individual SNP were associated with ASDs and showed a male bias, even after correction for multiple testing (SNP allele: P = 0.048, haplotype:P = 0.032). Simultaneously, none of these 7 known rare mutation of NLGN3 and NLGN4X genes was identified, neither in our patients with ASDs nor controls, giving further evidence that these known rare variants might be not enriched in Chinese Han cohort.
  
  
  CONCLUSIONS
  The present study provides initial evidence that a common variant in NLGN3 gene may play a role in the etiology of ASDs among affected males in Chinese Han population, and further supports the hypothesis that defect of synapse might involvement in the pathophysiology of ASDs.
authors.affiliation: Department of Pediatric Health Care, Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
authors.forename: Jindan
authors.initials: J
authors.lastname: Yu
authors.forename: Xue
authors.initials: X
authors.lastname: He
authors.forename: Dan
authors.initials: D
authors.lastname: Yao
authors.forename: Zhongyue
authors.initials: Z
authors.lastname: Li
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Zhengyan
authors.initials: Z
authors.lastname: Zhao
mesh_terms: D044466:Asian People / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics*; D016022:Case-Control Studies; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics*; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000235:genetics*; D002675:Child, Preschool; D005260:Female; D056726:Genetic Association Studies / Q000379:methods; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012727:Sex Characteristics
chemical_list: D002352:Carrier Proteins; D015816:Cell Adhesion Molecules, Neuronal; D008565:Membrane Proteins; C430845:NLGN4X protein, human; D009419:Nerve Tissue Proteins; C098004:neuroligin 3