[Single nucleotide polymorphisms of promoter of human leukocyte antigen-DQB1 alleles in Chinese Han patients with Vogt-Koyanagi-Harada syndrome].
OBJECTIVE
To investigate the single nucleotide polymorphism of the promoter of HLA-DQB1(QBP) in Chinese Han patients with Vogt-Koyanagi-Harada syndrome.


METHODS
Case-control design was applied. Eighty-eight Chinese Han patients with Vogt-Koyanagi-Harada syndrome and 88 non-Vogt-Koyanagi-Harada syndrome controls were admitted. DNA was extracted from the peripheral white blood cells of the subjects by the phenol-chloroform method. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and clone-sequencing were applied to determine the sequences of the promoter of HLA-DQB1. Chromans and Bioedit software were used to analyze the sequences of the promoter of HLA-DQB1. Chi-square test and Fisher exact test were applied to compare the frequencies of bands of QBPs and SNPs for the two groups.


RESULTS
Sixteen band patterns of HLA-QBP were shown by polyacrylamide gel electrophoresis (PAGE). The band frequencies of QBPb (corresponding gene sequence was QBP2.1 + 77C > A, chi2 = 26.01, Pc < 0.001) and QBPl (corresponding gene sequence was QBP3.3, chi2 = 16.99, Pc < 0.001) were significantly higher in patients with Vogt-Koyanagi-Harada syndrome than that in normal controls (Pc < 0.001). However, the frequencies of QBPg (corresponding gene sequence was QBP3.1, chi2 = 12.10, Pc < 0.05) and QBPn (corresponding gene sequence was QBP6.1 + 39G > A, chi2 = 14.64, Pc < 0.05) were significantly lower in patients with Vogt-Koyanagi-Harada syndrome than those of the controls. Twelve SNPs were found in all subjects. The frequency of C allele at position -189C/A in patients with Vogt-Koyanagi-Harada syndrome was significantly higher than that in controls (chi2 = 45.92, P = 0.000). However, the frequency of G allele at position -227G/A in patients with Vogt-Koyanagi-Harada syndrome was significantly lower as compared with that in the normal controls (chi2 = 15.63, P = 0.000).


CONCLUSIONS
C allele of -189C/A is a genetically susceptible factor of Vogt-Koyanagi-Harada syndrome and G allele of -227G/A is the protective factor of Vogt-Koyanagi-Harada syndrome.
Min
Han-yi
HY
Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing 100730, China.
Niu
Ni-fang
NF
Liu
Ying
Y
Zhang
Mei-fen
MF
Zhu
Xi-lin
XL
Zhao
Jia-liang
JL
D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D044466:Asian People / Q000235:genetics; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D006683:HLA-DQ Antigens / Q000235:genetics*; D059866:HLA-DQ beta-Chains; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D014607:Uveomeningoencephalitic Syndrome / Q000208:ethnology / Q000235:genetics* / Q000276:immunology; D055815:Young Adult
D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen