Multiple sclerosis in the Orkney and Shetland Islands. III: Histocompatibility determinants

Area of Science:

• Immunogenetics
• Neurology
• Epidemiology

Background:

• Multiple sclerosis (MS) is a neurological disease with a high prevalence in the Orkney Islands.
• The role of specific human leukocyte antigen (HLA) genes in MS etiology is under investigation.
• Previous theories suggest a link between certain histocompatibility antigens and MS.

Purpose of the Study:

• To investigate the association between specific HLA antigens and MS in a high-prevalence population.
• To examine the linkage disequilibrium of HLA antigens and B-cell alloantigens in MS patients and controls.
• To evaluate the consistency of findings with existing etiological theories of MS.

Main Methods:

• Histocompatibility testing was conducted on 48 MS patients and two control groups from the Orkney Islands.
• Frequencies of HLA-A3, HLA-B7, and DW2 were compared between patients and controls.
• The prevalence of B-cell alloantigen (B-cell 4) was assessed.
• Linkage analysis was performed for HLA-B7, DW2, and B-cell 4 in both groups.

Main Results:

• HLA-A3, HLA-B7, and DW2 frequencies were similar in MS patients and controls.
• HLA-B7 was significantly more frequent in female MS patients than in male MS patients.
• B-cell 4 showed comparable frequency in patients and controls.
• Strong linkage between HLA-B7, DW2, and B-cell 4 was observed in controls, particularly female controls, but not in patients.

Conclusions:

• The observed HLA antigen frequencies do not support theories directly linking these specific histocompatibility antigens to the etiology of multiple sclerosis.
• Sex-specific differences in HLA-B7 frequency warrant further investigation but do not confirm a primary etiological role.
• The lack of linkage disequilibrium in patients suggests MS development may disrupt or not be influenced by these specific genetic associations.