Background: Multiple sclerosis (MS) is known as chronic inflammatory causes demyelination and results in neurodegenerative disease in central nervous system (CNS), which is known with progressive disability. MS is accepted and is a multifactorial disorder that is a result of genetic and environmental factors interaction. The set of genes coding for MHC (major histocompatibility complex) molecules exert the effect on disease development. HLA-A*03 (HLA-A3) is one of HLA class I alleles, which is associated with MS. Objectives: Our goal is to survey the frequency of this allele in MS patients from the Khuzestan province. Methods: HLA-A*03 alleles association was investigated in 200 MS patients in the province of Khuzestan then compared with 195 healthy controls. HLA-typing was performed by polymerase chain reaction (PCR) amplification with SSP-PCR method. Results: Frequency of HLA-A*03 was significant among MS patients (47% vs. 26%, P < 0.001). There was no significant correlation among this allele and sex, course of disease, initial symptoms, and expanded disability status scale (EDSS). Conclusions: Our findings suggested that HLA-A*03 allele has a significant association with MS, which is in line with other studies, and also confirmed that the presence of this allele could increase the risk of MS. Furthermore, positive association between the HLA-A*03 allele and the Arab population in the province of Khuzestan was found. CIS patients followed up for three years demonstrated that all patients were converted to RRMS.

Introduction: There is accumulating evidence that the MHC gene variants are associated with some autoimmune disease. This recent publication on MHC population frequencies included a number of tables characterizing the frequency alleles and haplotypes in Khuzestan province. Identification of HLA alleles is helpful in anthropological, transplantation and disease studies, Investigating the frequency and association of HLA-DRB1*1501, -DQA1*0102, -DQB1*0602, -DRB5*01 and -A*0301 alleles and haplotypes in normal population according to gender and ethnicity, were the aim of this study. Methods:The frequency distribution of HLA DRB1*1501, DQA1*0102, DQB1*0602, DRB5*01 and A*0301 were studied in Iranian normal population of Khuzestan province analyzing by polymerase chain reaction using specific sequence primers (PCR-SSP) method in 242 healthy blood donors without any disease. We also examined the relationship of genotypes with gender and ethnic. Results: DRB1*1501 as the most frequent DRB allele had frequency of 42.85%. In contrast, the allelic frequency of DRB5*01 was very low (21.5%). In the HLA alleles DQA1*0102 was the most prevalent variant (71%). fifty percent of the population was positive with DQB1*0602 allele. Interestingly, it was found that DQA1*0102 +-DRB5*01 -haplotype was associated with gender and this haplotype was associated with ethnicity, too. The most frequent two, three, four and five allelic haplotypes were DRB5*01 Conclusions:The results of allele frequencies are consistent with some other studies. Our recent study gives a new insights into the immunogenetic map and HLA genetic profile of normal population in Khuzestan province, southwest of Iran, confirming the DQA1*0102 +-DRB5*01 -haplotype association with sex and ethnicity in a previously unreported population. So our results encourage future research to investigate the potential functional relevance of these haplotypes.