Familial amyloid polyneuropathy type I (FAP-I) is caused by a mutant transthyretin (TTR V30M) produced by liver, and orthotopic liver transplantation (OLT) is a widely accepted treatment for stopping the major production of TTR V30M.
Machado-Joseph disease [MJD, also spinocerebellar ataxia type 3 (SCA3)] and familial amyloid polyneuropathy type I (FAP-I or ATTR V30M) are neurodegenerative disorders, inherited in an autosomal dominant fashion, which have a high prevalence in Portugal, probably due to a founder effect.
It is a systemic amyloidosis caused by an amyloidogenic variant TTR (ATTR), of which the methionine for valine at position 30 (ATTR Val30Met) gives rise to a fatal neuropathic amyloidosis.