title: Neurotransmitter systems and neurotrophic factors in autism: association study of 37 genes suggests involvement of DDC.
abstract: OBJECTIVE
  Neurotransmitter systems and neurotrophic factors can be considered strong candidates for autism spectrum disorder (ASD). The serotoninergic and dopaminergic systems are involved in neurotransmission, brain maturation and cortical organization, while neurotrophic factors (NTFs) participate in neurodevelopment, neuronal survival and synapses formation. We aimed to test the contribution of these candidate pathways to autism through a case-control association study of genes selected both for their role in central nervous system functions and for pathophysiological evidences.
  
  
  METHODS
  The study sample consisted of 326 unrelated autistic patients and 350 gender-matched controls from Spain. We genotyped 369 tagSNPs to perform a case-control association study of 37 candidate genes.
  
  
  RESULTS
  A significant association was obtained between the DDC gene and autism in the single-marker analysis (rs6592961, P = 0.00047). Haplotype-based analysis pinpointed a four-marker combination in this gene associated with the disorder (rs2329340C-rs2044859T-rs6592961A-rs11761683T, P = 4.988e-05). No significant results were obtained for the remaining genes after applying multiple testing corrections. However, the rs167771 marker in DRD3, associated with ASD in a previous study, displayed a nominal association in our analysis (P = 0.023).
  
  
  CONCLUSIONS
  Our data suggest that common allelic variants in the DDC gene may be involved in autism susceptibility.
authors.affiliation: Departament de Genètica, Facultat de Biologia, Universitat de Barcelona , Spain.
authors.forename: Claudio
authors.initials: C
authors.lastname: Toma
authors.forename: Amaia
authors.initials: A
authors.lastname: Hervás
authors.forename: Noemí
authors.initials: N
authors.lastname: Balmaña
authors.forename: Marta
authors.initials: M
authors.lastname: Salgado
authors.forename: Marta
authors.initials: M
authors.lastname: Maristany
authors.forename: Elisabet
authors.initials: E
authors.lastname: Vilella
authors.forename: Francisco
authors.initials: F
authors.lastname: Aguilera
authors.forename: Carmen
authors.initials: C
authors.lastname: Orejuela
authors.forename: Ivon
authors.initials: I
authors.lastname: Cuscó
authors.forename: Fátima
authors.initials: F
authors.lastname: Gallastegui
authors.forename: Luis Alberto
authors.initials: LA
authors.lastname: Pérez-Jurado
authors.forename: Rafaela
authors.initials: R
authors.lastname: Caballero-Andaluz
authors.forename: Yolanda de
authors.initials: Yd
authors.lastname: Diego-Otero
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Guzmán-Alvarez
authors.forename: Josep Antoni
authors.initials: JA
authors.lastname: Ramos-Quiroga
authors.forename: Marta
authors.initials: M
authors.lastname: Ribasés
authors.forename: Mònica
authors.initials: M
authors.lastname: Bayés
authors.forename: Bru
authors.initials: B
authors.lastname: Cormand
mesh_terms: D000293:Adolescent; D000328:Adult; D001142:Aromatic-L-Amino-Acid Decarboxylases / Q000235:genetics*; D001321:Autistic Disorder / Q000453:epidemiology / Q000235:genetics* / Q000503:physiopathology; D002262:Carboxy-Lyases; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006239:Haplotypes; D006801:Humans; D008297:Male; D009414:Nerve Growth Factors / Q000235:genetics*; D018377:Neurotransmitter Agents / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D013030:Spain / Q000453:epidemiology; D055815:Young Adult
chemical_list: D005819:Genetic Markers; D009414:Nerve Growth Factors; D018377:Neurotransmitter Agents; D002262:Carboxy-Lyases; C477392:L-3,4-dihydroxyphenylalanine decarboxylase, Bombyx mori; D001142:Aromatic-L-Amino-Acid Decarboxylases