Association of a missense mutation of the laminin alpha2 gene with tuberculoid type of leprosy in Indonesian patients.

Leprosy, an infection caused by Mycobacterium leprae, has a specific tropism for the myelinating Schwann cells of peripheral nerves. Recently, the G domain of laminin alpha2 has been shown to be a mediator for M. leprae to bind to alpha-dystroglycan in Schwann cells. In order to analyse the association of leprosy with the mediator, three genetic polymorphisms encoding the G domain of the laminin alpha2 chain were analysed by direct sequencing in 53 leprosy patients and 58 healthy contact individuals from Indonesia. There was no significant difference in the incidence of the polymorphisms between patients and non-patients. Remarkably, it was found that a missense mutation (T7809C) substituting valine with alanine (V2587A) was found to be more frequent in the tuberculoid type than in the lepromatous type leprosy. It is supposed that this missense mutation is one of the determinant factors in the early onset of peripheral nerve damage in Indonesian tuberculoid leprosy patients.