Apolipoprotein E and alpha-1-antichymotrypsin polymorphisms in sporadic inclusion body myositis

Sporadic inclusion body myositis (s-IBM) is a progressive muscle disease of unknown aetiology. Characteristically, intracellular amyloid deposits are detectable, including beta-amyloid precursor protein, phosphorylated tau, alpha1-antichymotrypsin (alpha1-ACT) and apolipoprotein E (ApoE). Polymorphisms and mutations of the encoding genes have been identified in a variety of neurodegenerative diseases including Alzheimer's disease (AD). Beside other factors, polymorphisms may lead to protein accumulation in both diseases. In particular, polymorphisms within the ApoE and alpha1-ACT gene have been implicated in the aetiology of AD and s-IBM. We analysed ApoE and alpha1-ACT gene polymorphisms in 35 s-IBM patients. We could not identify any statistical significant correlation between distinct ApoE and alpha1-ACT genotypes and the risk of developing s-IBM. Additionally, ApoE and alpha1-ACT genotypes seem not to influence the onset age of s-IBM. A combination of different alpha1-ACT and ApoE genotypes appears not to enhance the risk of developing s-IBM. Therefore, allelic variations of alpha1-ACT and ApoE are unlikely to be genetic key factors in the aetiology of s-IBM.