We describe two different novel mutations in the PAX3 gene, detected in two families with cases of Waardenburg syndrome type I (WSI). The missense mutation detected in one family involved a single substitution in exon 2 (c.142 G > T) and was present both in the affected individual and in his clinically normal father. The mutation found in the second family consisted of a deletion of 13 bases, c.764-776del(TTACCCTGACATT), in exon 5.

OBJETIVO: comparar as características clínicas de doença priônica com as da demência frontotemporal e parkinsonismo associada ao cromossoma 17 (FTDP-17). FUNDAMENTOS: doenças priônicas não são usualmente incluídas no diagnóstico diferencial da FTDP-17 porque a doença de Creutzfeldt-Jakob (DCJ), a mais comum entre as doenças priônicas hereditárias, frequentemente manifesta-se como demência rapidamente progressiva. Por outro lado, a FTDP-17 apresenta-se insidiosamente na quinta década, com alterações do comportamento e sinais parkinsonianos. MÉTODO: apresentamos as características clínicas de 12 membros de uma família com DCJ associada à mutação de ponto no codon 183 do gene da proteína priônica. RESULTADOS: os sintomas iniciaram-se aos 44.0 ± 3.7 anos e a duração até o óbito foi de dois a cinco anos. Alterações do comportamento foram os sintomas iniciais mais frequentes. Nove pacientes foram atendidos inicialmente por psiquiatras. Oito pacientes manifestaram sinais parkinsonianos. CONCLUSÃO: as características clínicas apresentam considerável semelhança com as descritas na FTDP-17.

OBJECTIVE: To compare the clinical features of a familial prion disease with those of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). BACKGROUND: Prion diseases are not usually considered in the differential diagnosis of FTDP-17, since familial Creutzfeldt-Jakob disease (CJD), the most common inherited prion disease, often manifests as a rapidly progressive dementia. Conversely, FTDP-17 usually has an insidious onset in the fifth decade, with abnormal behavior and parkinsonian features. METHOD: We present the clinical features of 12 patients from a family with CJD associated with a point mutation at codon 183 of the prion protein gene. RESULTS: The mean age at onset was 44.0 ± 3.7; the duration of the symptoms until death ranged from two to nine years. Behavioral disturbances were the predominant presenting symptoms. Nine patients were first seen by psychiatrists. Eight patients manifested parkinsonian signs. CONCLUSION: These clinical features bear a considerable resemblance to those described in FTDP-17.