[Study on the genetic association between DRB3 and DRB1 loci in the human MHC region and psychotic symptoms of schizophrenia].
OBJECTIVE
The genomic region of the human major histocompatibility complex (MHC) is located in the short arm of chromosome 6 (6p). Linkage studies have shown that the 6p region may contain a gene for schizophrenia, the MHC region has thus become particularly important in searching for the schizophrenia susceptibility gene. The present study was designed to investigate the genetic association of DRB3 and DRB1 genes with psychotic symptoms of schizophrenia.


METHODS
PCR-based restriction fragment length polymorphism (RFLP) analysis was applied to genotype two single nucleotide polymorphisms (SNPs) located in the DRB3 locus and in the DRB1 one in 116 Chinese Han family trios consisting of fathers, mothers and affected offspring with schizophrenia. Chi-square (chi(2)) test and haplotype-based relative risk (HRR) analysis were used on genotyping data.


RESULTS
Data on HRR analysis did not show a genetic association either between the DRB3 locus and schizophrenia or between the DRB1 locus and the illness. However, the SNP rs707954, a G to T base change, present in the DRB1 locus showed strong association with idea of reference (chi(2) = 5.484, df = 1, P = 0.019), while the genotype of rs707954 showed an association with idea of reference (chi(2) = 6.771, df = 2, P = 0.034) as will as with apathy (chi(2) = 12.110, df = 4, P = 0.017).


CONCLUSIONS
DRB1 locus seemed likely to be associated with psychotic symptoms as idea of reference and apathy. Further studies were necessary to reveal the relations between DRB1 gene or nearby locus with its susceptibility to schizophrenia.
Yu
Ya-qin
YQ
Center for Genomic Medicine, School of Public Health, Jilin University, Changchun 130021, China.
Yu
Qiong
Q
Guo
Ying-jun
YJ
Sang
Hong
H
Shi
Jie-ping
JP
Liu
Shu-zheng
SZ
Wei
Jun
J
D002874:Chromosome Mapping; D002896:Chromosomes, Human, Pair 6; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006684:HLA-DR Antigens / Q000235:genetics*; D059811:HLA-DRB1 Chains; D059826:HLA-DRB3 Chains; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide; D012559:Schizophrenia / Q000235:genetics*
D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; D059826:HLA-DRB3 Chains