Association study of polymorphisms in synaptic vesicle-associated genes, SYN2 and CPLX2, with schizophrenia.
BACKGROUND
The occurrence of aberrant functional connectivity in the neuronal circuit is one of the integrative theories of the etiology of schizophrenia. Previous studies have reported that the protein and mRNA levels of the synapsin 2 (SYN2) and complexin 2 (CPLX2) genes were decreased in patients with schizophrenia. Synapsin 2 and complexin 2 are involved in synaptogenesis and the modulation of neurotransmitter release. This report presents a study of the association of polymorphisms of SYN2 and CPLX2 with schizophrenia in the Korean population.


METHODS
Six single nucleotide polymorphisms (SNPs) and one 5-bp insertion/deletion in SYN2 and five SNPs in CPLX2 were genotyped in 154 Korean patients with schizophrenia and 133 control patients using direct sequencing or restriction fragment length polymorphism analysis. An intermarker linkage disequilibrium map was constructed for each gene.


RESULTS
Although there was no significant difference in the genotypic distributions and allelic frequencies of either SYN2 or CPLX2 polymorphisms between the schizophrenia and control groups, the two-way haplotype analyses revealed significant associations with the disease (P < 0.05 after Bonferroni correction). The three-way haplotype analyses also revealed a significant association of SYN2 with schizophrenia (P < 0.001 after Bonferroni correction).


CONCLUSIONS
These results suggest that both SYN2 and CPLX2 may confer susceptibility to schizophrenia in the Korean population.
Lee
Hee Jae
HJ
Medical Science Institute, Kangwon National University, Chunchon, Republic of Korea. heejaelee@kangwon.ac.kr
Song
Ji Young
JY
Kim
Jong Woo
JW
Jin
Sheng-Yu
SY
Hong
Mi Suk
MS
Park
Jin Kyoung
JK
Chung
Joo-Ho
JH
Shibata
Hiroki
H
Fukumaki
Yasuyuki
Y