Molecular analysis of a variant type of familial amyloidotic polyneuropathy showing cerebellar ataxia and pyramidal tract signs.
A Japanese family with atypical type I familial amyloidotic polyneuropathy (FAP) in Iiyama, Japan was studied. Most of the family members have dysfunctions in the central nervous system, in addition to typical symptoms of type I FAP. The transthyretin (TTR, also called prealbumin) gene of the atypical FAP(FAP-IY) was analyzed with recombinant DNA techniques and a RIA method. FAP-IY was found to have the mutation responsible for the methionine-for-valine substitution at position 30 of TTR, as in the case of typical type I FAP. However, analysis of DNA polymorphisms in the TTR locus showed that FAP-IY has a genetic background differing from that of the typical type I FAP. These observations lead to the consideration that a genetic factor(s) involved in the dysfunction of the central nervous system may locate in a chromosome region in close proximity to the TTR gene.
D000686:Amyloidosis / Q000235:genetics*; D005796:Genes; D006801:Humans; D007564:Japan; D009154:Mutation; D010375:Pedigree; D011115:Polyneuropathies / Q000235:genetics*; D011228:Prealbumin / Q000235:genetics; D011712:Pyramidal Tracts; D013132:Spinocerebellar Degenerations / Q000235:genetics*
D011228:Prealbumin