Relationship between HLA-DRB1*11/15 genotype and susceptibility to multiple sclerosis in IRAN

Background & objectives: Analysis of the role of different alleles of human leukocyte antigen (HLA) in multiple sclerosis (MS) patients is necessary in many populations and geographical areas. The aim of the present study was to investigate the frequency of HLA-DRB1 genes and its influence on susceptibility to MS, comparing with that in control group. Design and setting: Two groups of case-control of multiple sclerosis patients referred to clinic at Khatam hospitals were studied. The first group consisted of 73 multiple sclerosis patients and the second group comprised 40 healthy volunteers with no known history of MS, living in Tehran. Patients and methods: The sample population consisted of 73 consecutive non-selected patients diagnosed with MS according to the McDonald criteria (2010) at the outpatient clinic for multiple sclerosis, 62 (85%) presented with RRMS and 11(15%) with SPMS. The frequency of HLA-DRB1 alleles was determined in 73 MS patients (with age of 18-56) and 40 healthy subjects in Iran. These consisted of 57 females and 16 males. HLA-DRB1 allele types were identified by polymerase chain reaction products of 24 pair primers for low resolution SSP typing (PCR-SSP). Results: The HLA-DRB1* 11/15 genotype was detected highest (6 times) in patients compare to normal control population (p-value 0.062), whereas the DRB1 4/11 genotype was detected highest (4 times) in controls compare to MS patients (p-value 0.033). The data showed that HLA-DRB1*03 is significantly more in patients compare to control normal people (p-value 0.0021) as well as DRB1 14 and 16 are significantly more in control normal people, compare to MS patients (p-values 0.0789 and 0.035). Conclusion: Allele frequency among patients with positive history of multiple sclerosis disease showed that DRB1 11 allele has a significantly low rate in MS patients with positive history compare to other patients. In contrast DRB1 15 allele has a significantly high rate in MS patients with positive history compare to other patients. The frequencies of other alleles were not significantly different between the MS patients and the control group. The frequency of the HLA-DRB1* 11/15 genotype detected in the present study showed that this genotype is partially significant factor for MS susceptibility and development in Iran. (C) 2014 Elsevier B.V. All rights reserved.