n :  ataxia of any of several phenotypically variant forms that are inherited as autosomal dominant traits, have an onset early in adult life, tend to occur in families of Portuguese and esp. Azorean ancestry, and are characterized by progressive degeneration of the central nervous system
 
Ma•cha•do and Jo*seph (fl 1970s), Azorean-Portuguese families. A hereditary form of ataxia was found in the Machado family of Massachusetts and described by K. K. Nakano et al in an article published in 1972. In that same year a variant form of the disease was found in the Joseph family of California and described in a separate article published by B. I. Woods and H. H. Schaumburg. The disease has been traced to Joseph Antone, a Portuguese seaman who emigrated from the Azores to California in 1845.
 
     
 
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