Polymorphism screening of brain-expressed FABP7, 5 and 3 genes and association studies in autism and schizophrenia in Japanese subjects.
Fatty acid-binding protein (FABP) gene family encode fatty acid-binding proteins and consist of at least 12 members, of which FABP7, 5 and 3 are expressed in the brain. We previously showed that FABP7 is associated with schizophrenia and bipolar disorder. Recently, genetic overlap between autism and schizophrenia has been reported. Therefore, in this study, we set out to examine the possible roles of brain-expressed FABPs in autism, focusing primarily on potentially functional polymorphisms (that is, missense polymorphisms). First, we resequenced the three genes using 285 autism samples. We identified 13 polymorphisms, of which 7 are novel. Of the novel single-nucleotide polymorphisms (SNPs), two are missense mutations, namely, 376G>C (Val126Leu) in FABP7 and 340G>C (Gly114Arg) in FABP5. Second, we tested for the genetic association of four missense SNPs with autism and schizophrenia, but failed to detect significant results. Finally, as a web-based algorithm predicts that the 8A>G (Asp3Gly; rs17848124) in FABP3 is 'probably damaging', we estimated the possible impact of this SNP, and found that the loss of charge and salt bridge, caused by the Asp3-to-Gly3, may affect stability of the FABP3 protein. Future searches for associated phenotypes with missense SNPs using larger samples are highly warranted.
Maekawa
Motoko
M
RIKEN Brain Science Institute, Saitama, Japan. mmaekawa@brain.riken.jp
Iwayama
Yoshimi
Y
Arai
Ryoichi
R
Nakamura
Kazuhiko
K
Ohnishi
Tetsuo
T
Toyota
Tomoko
T
Tsujii
Masatsugu
M
Okazaki
Yuji
Y
Osumi
Noriko
N
Owada
Yuji
Y
Mori
Norio
N
Yoshikawa
Takeo
T
D044466:Asian People / Q000235:genetics; D001321:Autistic Disorder / Q000235:genetics*; D001921:Brain / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D000074026:Fatty Acid Binding Protein 3; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D008297:Male; D008958:Models, Molecular; D020125:Mutation, Missense / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D012559:Schizophrenia / Q000235:genetics*; D017422:Sequence Analysis, DNA; D025521:Tumor Suppressor Proteins / Q000235:genetics* / Q000378:metabolism
D002352:Carrier Proteins; C493408:FABP3 protein, human; C493412:FABP5 protein, human; C107608:FABP7 protein, human; D000074026:Fatty Acid Binding Protein 3; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D025521:Tumor Suppressor Proteins