Saturday, June 25, 2011

is multiple sclerosis genetic

is multiple sclerosis genetic
The Answer is yes..
See below for information..

The Role of Genetics in MS

Genetic factors can affect an individual’s immune system and its response to foreign antigens. Genes determine the variety of MHC molecules that individuals carry on their cells. Genes also influence the array of T cell receptors present on T cells. Some MHC genes are associated with autoimmune diseases, such as MS. However, genes are not the only factors involved determining a person’s susceptibility to an autoimmune disease. For example, some individuals who carry disease-associated MHC molecules on their cells will not develop an autoimmune disease (Haines et al., 1996; DeJager & Hafler, 2004).
New findings show that variants of the interferon gamma gene located on chromosome 12 might be related to susceptibility to MS (Kantarci et al., 2005). These variants present differently in males and females, and it might be related to the high prevalence of multiple sclerosis in women (Kantarci et al., 2005). Therefore, probably multiple different genes are related to MS susceptibility. In 1996, researchers reported that 20 locations in the genome may contribute to MS susceptibility (National MS Society, 2002). In summary, scientists believe that a person is susceptible to developing MS only if a specific combination of genes is inherited.

Epidemiological findings support a polygenic hereditary predisposition to MS. Human leukocyte antigen (HLA) DR2 carriership is associated with an increased risk for MS. HLA-DR2 is one of the definite genetic associations for MS. Sixty percent (60%) of MS patients in Northern Europe are DRB1 1501 (DR2 haplotype) positive compared with 30% in healthy individuals. Therefore, HLA-DR2 is associated with a cluster of alleles, which have a two-fold increased risk for developing MS. The risk by this haplotype is
small, and it is neither necessary nor sufficient for development of MS (DeJong et al., 2002). There is a blood test that detects presence or absence of HLA-DR2. But because the data is not compelling, this test is not routinely recommended in clinical practice.

Multiple sclerosis is more common in women than in men at a ratio of 2:1. A recent study showed that interferon gamma (?) expression varies by gender. Interferon ? is associated with a worsening effect on MS. Genetic variants that affect expression of interferon gamma might influence the susceptibility to MS and the severity of the disease. In general, higher interferon ? expression leads to an increased Th-1 cell response that corresponds with higher susceptibility to MS. The interferon ? gene is located on chromosome 12. This study suggests that men have the gene variant that causes high levels of interferon gamma less often than women (Kantarci et al., 2005). In summary, polymorphism of interferon gamma gene may contribute to differences in susceptibility to MS.

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