Multiple Sclerosis (MS) and Serotype HLA-DR2

MS and Serotype HLA-DR2

MS and Serotype HLA-DR2 have an allelic dose-effect relationship, with HLA-DR2 being a predisposing factor in the demyelinating autoimmune illness of the central nervous system. The HLA-DR2 allele is found on chromosome 6 in the major histocompatibility complex (MHC), and its presence is a predictive factor in genetic testing and counseling (Rhodes, 2011). The application is based on the knowledge that HLA DR2 increases the risk and course of sporadic and familial MS, with heterozygous and homozygous carriers of the allele having an increased chance of developing MS. They also experience worse episodes of the debilitating symptoms such as muscle spasticity, loss of cognitive functions, fatigue, and bowel and bladder dysfunction, among other manifestation when compared with HLA-DR2-negative persons.

Dose Effects of HLA-DR2

Kesselring, Comi, & Thompson (2010) confirm the dose effects, where they note that HLA-DR2 increases susceptibility to disease by fourfold. The genetic predisposition is also established by the current trends, where both epidemiologic and laboratory studies have shown that the prevalence of MS follows an ethnoracial and familial clustering. For instance, while the Icelanders and Scandinavians report the highest prevalence rates, MS is uncommon among Africans, Asians, Amerindians, and Aboriginal groups from Australians and New Zealand (Cohen & Rudick, 2011). The disparities arise from polymorphism, where some groups do not carry the class II MHC alleles. The association is also echoed by findings from the Genome-Wide Association Studies (GWAS), where the laboratory tests and polygenic models have confirmed that HLA class II genes are a quantifiable trait in MS etiopathogenesis (Cohen & Rudick, 2011). Despite the allelic association, Serotype HLA-DR2 should not be the only primary in the diagnosis. The view is supported by the fact that MS is epistatic, where the disease has multifaceted risk factors (Cohen & Rudick, 2011).

References

Cohen, J. A., & Rudick, R. A. (Eds.). (2011). Multiple sclerosis therapeutics. Cambridge University Press.

Kesselring, J., Comi, G., & Thompson, A. J. (Eds.). (2010). Multiple sclerosis: recovery of function and neurorehabilitation. Cambridge University Press.

Rhodes, M. A. (2011). CCSVI as the Cause of Multiple Sclerosis: The Science Behind the Controversial Theory. McFarland.