J Korean Med Sci.  2002 Jun;17(3):366-370. 10.3346/jkms.2002.17.3.366.

Association of MICA Polymorphism with HLA-B51 and Disease Severity in Korean Patients with Behcet's Disease

• Park SH
• Park KS
• Seo YI
• Min DJ
• Kim WU
• Kim TG
• Cho CS
• Mok JW
• Park KS
• Kim HY

• KMID: 1101552
• DOI: http://doi.org/10.3346/jkms.2002.17.3.366

Abstract

The HLA-B51 allele is known to be associated with Behcet's disease (BD) in many ethnic group. However, it has not yet been clarified whether the HLA-B51 gene itself is the pathogenic gene related to BD or whether it is some other gene in linkage disequlibrium with HLA-B51. Recently, the Triplet repeat (GCT/AGC) polymorphism in transmembrane region of the MHC class I chain-related A (MICA) gene was identified. To investigate the association of MICA with BD, we studied the MICA polymorphism in 108 Korean BD patients and 204 healthy controls in relation to the presence of HLA-B51 and clinical manifestations. The triplet repeat polymorphism was determined by polymerase chain reaction (PCR)-denaturing polyacrylamide gel electrophoresis (PAGE). The phenotype frequency of the MICA*A6 allele (relative risk, RR=2.15, p=0.002) and HLA-B51(RR=1.87, p=0.022) were significantly increased in the Korean patients with BD. A strong linkage disequilibrium was observed between the MICA*A6 and HLA-B51 in both the patients with BD and control subjects. Stratification analysis showed that MICA*A6 homozygosity was strongly associated with BD in the HLA-B51-negative population, and HLA-B51 was also associated with MICA*A6-negative population. In conclusion, MICA*A6 rather than HLA-B51 was strongly associated with Korean patients with BD, and the MICA*A6 allele is a useful susceptibility marker of BD, especially in the HLA-B5-negative

Keyword

MICA Polymorphism; Behcet's Disease; HLA-B51

MeSH Terms

Adult
Behcet Syndrome/*genetics
Genetic Predisposition to Disease
HLA-B Antigens/*genetics
Histocompatibility Antigens Class I/*genetics
Humans
Korea
Microsatellite Repeats
Middle Aged
Phenotype
*Polymorphism, Genetic
Severity of Illness Index