title: HLA-DR2 dose effect on susceptibility to multiple sclerosis and influence on disease course.
abstract: Models of disease susceptibility in multiple sclerosis (MS) often assume a dominant action for the HLA-DRB1*1501 allele and its associated haplotype (DRB1*1501-DQB1*0602 or DR2). A robust and phenotypically well-characterized MS data set was used to explore this model in more detail. A dose effect of HLA-DR2 haplotypes on MS susceptibility was revealed. This observation suggests that, in addition to the role of HLA-DR2 in MS, two copies of a susceptibility haplotype further increase disease risk. Second, we report that DR2 haplotypes modify disease expression. There is a paucity of benign MS and an increase of severe MS in individuals homozygous for DR2. Concepts of the molecular mechanisms that underlie linkage and association of the human leukocyte antigen (HLA) region to MS need to be revised to accommodate these data.
authors.affiliation: Department of Neurology, University of California at San Francisco, San Francisco, CA, USA.
authors.forename: L F
authors.initials: LF
authors.lastname: Barcellos
authors.forename: J R
authors.initials: JR
authors.lastname: Oksenberg
authors.forename: A B
authors.initials: AB
authors.lastname: Begovich
authors.forename: E R
authors.initials: ER
authors.lastname: Martin
authors.forename: S
authors.initials: S
authors.lastname: Schmidt
authors.forename: E
authors.initials: E
authors.lastname: Vittinghoff
authors.forename: D S
authors.initials: DS
authors.lastname: Goodin
authors.forename: D
authors.initials: D
authors.lastname: Pelletier
authors.forename: R R
authors.initials: RR
authors.lastname: Lincoln
authors.forename: P
authors.initials: P
authors.lastname: Bucher
authors.forename: A
authors.initials: A
authors.lastname: Swerdlin
authors.forename: M A
authors.initials: MA
authors.lastname: Pericak-Vance
authors.forename: J L
authors.initials: JL
authors.lastname: Haines
authors.forename: S L
authors.initials: SL
authors.lastname: Hauser
mesh_terms: D018450:Disease Progression; D005260:Female; D018628:Gene Dosage; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006684:HLA-DR Antigens / Q000235:genetics; D015802:HLA-DR2 Antigen / Q000235:genetics*; D059811:HLA-DRB1 Chains; D006239:Haplotypes; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000235:genetics* / Q000276:immunology / Q000503:physiopathology; D010641:Phenotype; D018570:Risk Assessment
chemical_list: D006684:HLA-DR Antigens; D015802:HLA-DR2 Antigen; D059811:HLA-DRB1 Chains