- Linkage disequilibrium at the Machado-Joseph disease/spinal cerebellar ataxia 3 locus: evidence for a common founder effect in French and Portuguese-Brazilian families as well as a second ancestral Portuguese-Azorean mutation. Stevanin, G., Cancel, G., Didierjean, O., Dürr, A., Abbas, N., Cassa, E., Feingold, J., Agid, Y., Brice, A. Am. J. Hum. Genet. (1995)