title: The importance of HLA DRB1 gene allele to clinical features and disability in patients with multiple sclerosis in Lithuania.
abstract: BACKGROUND
  The association of HLA DRB1 alleles with susceptibility to multiple sclerosis (MS) has been consistently reported although its effect on the clinical features and disability is still unclear probably due to diversity in ethnicity and geographic location of the studied populations. The aim of the present study was to investigate the influence of HLA DRB1 alleles on the clinical features and disability of the patients with MS in Lithuania.
  
  
  METHODS
  This was a prospective study of 120 patients with MS. HLA DRB1 alleles were genotyped using the polymerase chain reaction.
  
  
  RESULTS
  The first symptoms of MS in patients with HLA DRB1*15 allele manifested at younger age than in those without this allele (28.32 +/- 5.49 yrs vs. 30.94 +/- 8.43 yrs, respectively, p = 0.043). HLA DRB1*08 allele was more prevalent among relapsing-remitting (RR) MS patients than among patients with progressive course of MS (25.0% vs. 8.3%, respectively, chi^2 = 6.000, p = 0.05). MS patients with this allele had lower relapse rate than those without this allele (1.00 +/- 0.97 and 1.44 +/- 0.85, respectively, p = 0.043). Degree of disability during the last visit was lower among the patients with HLA DRB1*08 allele (EDSS score 3.15 +/- 1.95 vs. 4.49 +/- 1.96, p = 0.006), and higher among those with HLA DRB1*15 allele (EDSS score 4.60 +/- 2.10 vs.4.05 +/- 1.94, p = 0.047) compared to patients without these alleles but there were no significant associations between these alleles and the duration of the disease to disability. HLA DRB1*08 allele (OR = 0.18, 95% CI 0,039-0,8, p = 0.029) was demonstradet to be independent factor to take a longer time to reach an EDSS of 6, while HLA DRB1*01 allele (OR = 5.92, 95% CI 1,30-26,8, p = 0.021) was related in a shorter time to reach and EDSS of 6. Patients with HLA DRB1*08 allele had lower IgG index compared to patients without this allele (0.58 +/- 0.17 and 0.73 +/- 0.31, respectively, p = 0.04), and HLA DRB1*15 allele was more often found among MS patients with oligoclonal bands (OCBs) in cerebrospinal fluid than among those without OCBs (OR 2.3, CI 95% 1.017-5.301; p = 0.043).
  
  
  CONCLUSIONS
  HLA DRB1*15 allele was related with an earlier manifestation of the first MS symptoms, progressive course of the disease and higher degree of disability. HLA DRB1*08 allele was more prevalent among the RR MS patients and was associated with the lower rate of relapse, degree of disability and IgG index.
authors.affiliation: Department of Neurology, Academy of Medicine, Lithuanian University of Health Sciences, A, Mickeviciaus street 9, Kaunas LT 44307, Lithuania. rbalnyte@yahoo.com
authors.forename: Renata
authors.initials: R
authors.lastname: Balnyte
authors.forename: Daiva
authors.initials: D
authors.lastname: Rastenyte
authors.forename: Antanas
authors.initials: A
authors.lastname: Vaitkus
authors.forename: Dalia
authors.initials: D
authors.lastname: Mickeviciene
authors.forename: Erika
authors.initials: E
authors.lastname: Skrodeniene
authors.forename: Astra
authors.initials: A
authors.lastname: Vitkauskiene
authors.forename: Ingrida
authors.initials: I
authors.lastname: Uloziene
mesh_terms: D000328:Adult; D006233:Persons with Disabilities; D004569:Electroencephalography; D005074:Evoked Potentials, Visual; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D059811:HLA-DRB1 Chains / Q000235:genetics*; D006801:Humans; D008097:Lithuania / Q000453:epidemiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000134:cerebrospinal fluid / Q000150:complications* / Q000235:genetics*; D043025:Oligoclonal Bands / Q000134:cerebrospinal fluid; D010775:Photic Stimulation; D018709:Statistics, Nonparametric
chemical_list: D059811:HLA-DRB1 Chains; D043025:Oligoclonal Bands