LETTER TO JMG Association of an interleukin 1B gene polymorphism (−511) with Parkinson’s disease in Finnish patients

tion of proteins and loss of neurones in specific regions of the brain. The aetiology and pathogenesis of AD and PD still remain largely unknown. Evidence has emerged that immune mediated mechanisms may be important in the development of these disorders,1 2 and cytokine interleukin 1 (IL1) is one of the mediators suggested to be involved. The IL1 family comprises three proteins, the proinflamma-tory IL1α and IL1β and their inhibitor IL1 receptor antagonist (IL1Ra), which are encoded by the IL1A, IL1B, and IL1RN genes respectively.3 Since IL1 may have a role in AD4–8 and in PD,9 10 variation in the IL1A, IL1B, and IL1RN genes may be of importance in the development of these disorders. There is already some evidence in support of this, including the postu-lated association of the IL1A (−889) *2/*2 genotype with AD11 and the influence of the IL1B (−511) *1/*1 genotype on age a