A missense G209A mutation of the alpha-synuclein gene was recently described in a large Contursi kindred with Parkinson's disease (PD). The objective of this study is to determine if the mutation G209A of the alpha-synuclein gene was present in 10 Brazilian families with PD. PD patients were recruited from movement disorders clinics of Brazil. A family history with two or more affected in relatives was the inclusion criterion for this study. The alpha-synuclein G209A mutation assay was made using polymerase chain reaction and the restriction enzyme Tsp451. Ten patients from 10 unrelated families were studied. The mean age of PD onset was 42.7 years old. We did not find the G209A mutation in our 10 families with PD. Our results suggest that alpha-synuclein mutation G209A is uncommon in Brazilian PD families.593 B722724Polymeropoulos, M.H., Autosomal dominant Parkinson's disease and alpha-synuclein (1998) Ann Neurol, 44 (1 SUPPL.), pp. 63-64Polymeropoulos, M.H., Levadan, C., Leroy, E., Mutation in the alpha-synuclein gene identified in families with Parkinson's disease (1997) Science, 276, pp. 2045-2047Krüger, R., Kühn, W., Muller, T., Ala30Pro mutation in the gene encoding alpha-synuclein in Parkinson's disease (1998) Nat Genet, 18, pp. 106-108Chan, P., Tanner, C.M., Jiang, X., Langsten, J.W., Failure to find the alpha-synuclein gene missense mutation (G209A) in 100 patients with younger onset Parkinson's disease (1998) Neurology, 50, pp. 513-514Wang, W.W., Khajavi, M., Patel, B.J., Beach, J., Jankovic, J., Ashizawa, T., The G209A mutation in the α-synuclein gene is not detected in familial cases of Parkinson disease in non-Greek and/or Italian populations (1998) Arch Neurol, 55, pp. 1521-1523Vaughan, Jr., Durr, A., Tassin, J., Bereznai, B., Gasser, T., Bonifati, V., The a-synuclein Ala53Thr mutation is not a common cause of familial Parkinson's disease: A study of 230 European cases (1998) Ann Neurol, 44, pp. 270-273Chan, D.K.Y., Mellich, G., Cai, H., The α-synuclein gene and Parkinson disease in a Chinese population (2000) Arch Neurol, 57, pp. 501-503Gasser, T., Müller-Myhsok, B., Wszolek, Z.K., A susceptibility locus for Parkinson's disease maps to chromosome 2p13 (1998) Nat Genet, 18, pp. 262-265Farrer, M., Gwinn-Hardy, K., Muenter, M., A chromosome 4p haplotype segregating with Parkinson's disease and postural tremor (1999) Hum Mol Genet, 8, pp. 81-85Leroy, E., Boyer, R., Auburger, G., The ubiquitin pathway in Parkinson's disease (1998) Nature, 395, pp. 451-452Kitada, T., Askawa, S., Hattori, N., Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism (1998) Nature, 392, pp. 605-608Gasser, T., Genetics of Parkinson's disease (1998) Ann Neurol, 44 (1 SUPPL.), pp. 53-57Golbe, L.I., Di Iorio, G., Sanges, G., Lazzarini, A.M., LaSala, S., Bonavita, V., Clinical genetic analysis of Parkinson's disease in the Contursi kindred (1996) Ann Neurol, 40, pp. 767-775Gasser, T., Müller-Myhsok, B., Wszolek, Z.K., Genetic complexity and Parkinson's disease (1997) Science, 277, pp. 388-389Bennet, P., Nicholl, D.J., Absence of G209A mutation in alpha-synuclein gene in British families with Parkinson's disease (1998) Neurology, 50, p. 1183Ho, S.L., Kung, M.H.W., G209A mutation in the a-synuclein gene is rare and not associated with sporadic Parkinson's disease (1998) Mov Disord, 13, pp. 970-971Parsian, A., Racette, B., Zhang, Z.H., Mutation, sequence, analysis, and association of a-synuclein in Parkinson's disease (1998) Neurology, 51, pp. 1757-1759Waner, T.T., Schapira, A.H.V., The role of the a-synuclein gene mutation in patients with sporadic Parkinson's disease in the United Kingdom (1998) J Neurol Neurosurg Psychiatry, 65, pp. 378-379Farrer, M., Wavrant-De Vrieze, F., Crook, R., Low frequency of a-synuclein mutations in familial Parkinson's disease (1998) Ann Neurol, 43, pp. 394-397Vaughan, J., Farrer, M.J., Wszolek, Z.K., Sequencing of the alpha-synuclein gene in a large series of case of familial Parkinson's disease fails to reveal any further mutations (1998) Hum Mol Genet, 7, pp. 751-753Lücking, C.B., Dürr, A., Bonifati, V., Association between early-onset Parkinson's disease and mutations in the parkin gene (2000) N Engl J Med, 342, pp. 1560-1567