An investigation of NOS2A promoter polymorphisms in Australian multiple sclerosis patients.
As with other major autoimmune diseases, susceptibility to multiple sclerosis (MS) is believed to result from the complex interaction of a number of genes, each with modest effect. Extensive research of experimental autoimmune encephalomyelitis in mice and several direct MS studies have implicated NOS2A, which encodes the inducible form of nitric oxide synthase, and the genetic region encoding NOS2A, 17q11.2, has been identified in a number of genome wide screens as being potentially associated with MS. We investigated four single nucleotide polymorphisms in the proximal promoter region of NOS2A, in a case-control group of 100 Australian MS patients and 100 controls and in 203 MS patients and their unaffected parents. We found a trend toward excess transmission of the -277A allele (tag for the AGCC haplotype) to HLA-DRB1*1501-positive MS patients (P (uncorrected)=0.05). We initially discovered a trend toward over-representation of the AGCC haplotype in HLA-DRB1*1501-positive compared to HLA-DRB1*1501-negative MS patients in the case-control cohort. However, when combined with the probands from the transmission disequilibrium analysis, this trend was nullified. Nonetheless, despite the lack of significant evidence of association for the NOS2A promoter polymorphisms with MS, the gene remains an interesting candidate for MS susceptibility, particularly with regard to the HLA-DRB1*1501 haplotype.
Bugeja
Matthew J
MJ
The Institute for Immunology and Allergy Research, Westmead Millennium Institute, Westmead Campus, University of Sydney, Westmead NSW 2145, Australia.
Booth
David R
DR
Bennetts
Bruce H
BH
Heard
Robert N S
RN
Burgner
David
D
Stewart
Graeme J
GJ
D000483:Alleles; D001315:Australia; D016022:Case-Control Studies; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D015810:Linkage Disequilibrium; D009103:Multiple Sclerosis / Q000235:genetics*; D019001:Nitric Oxide Synthase / Q000235:genetics*; D052247:Nitric Oxide Synthase Type II; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic / Q000235:genetics*
D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C489631:HLA-DRB1*15:01 antigen; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II