Résumé
A late onset neurological syndrome in carriers of premutation in FMR1 gene was recently described. The condition was named fragile-X-associated tremor/ataxia syndrome (FXTAS) and includes intentional tremor, cerebellar ataxia, parkinsonism, and cognitive deficit. We ascertained the contribution of FMR1 premutation to the phenotypes ataxia, tremor and/or parkinsonism. Sixty-six men over 45 years old presenting these symptoms, isolated or combined, were tested. Also, 74 normal men, randomly chosen in the population, formed the control group. In the patient group, no premutation carrier was found, which is in agreement with other observed frequencies reported elsewhere (0-5% variation). No significant differences were found when comparing gray zone allele frequencies among target and control groups. The FXTAS contribution in patients with phenotypic manifestations of FXTAS was 15/748 (2%). The presence of gray zone alleles is not correlated with FXTAS occurrence.
Sujets)
Humains , Mâle , Adulte d'âge moyen , Ataxie/diagnostic , Maladie de Parkinson/diagnostic , Fréquence d'allèle , Protéine du syndrome X fragile/génétique , Tremblement/diagnostic , Allèles , Ataxie/physiopathologie , Ataxie/génétique , Ataxie/anatomopathologie , Études cas-témoins , Maladie de Parkinson/physiopathologie , Maladie de Parkinson/génétique , Maladie de Parkinson/anatomopathologie , Prédisposition génétique à une maladie , Tremblement/physiopathologie , Tremblement/génétique , Tremblement/anatomopathologieRésumé
Três cães, fêmeas, da raça Weimaraner apresentaram tremores corporais rítmicos generalizados a partir da primeira semana de vida. Outros dois cães, machos, da mesma ninhada não apresentaram alterações. Uma fêmea com quatro semanas de idade foi submetida à eutanásia e necropsiada. Macroscopicamente, observou-se no encéfalo pouca demarcação da substância branca em relação à cinzenta. Histologicamente havia acentuada vacuolização de toda a substância branca subcortical. A mielinização no sistema nervoso periférico estava normal. Os sinais clínicos, a idade de ocorrência e as lesões histológicas são compatíveis com a hipomielinogênese congênita descrita em cães
Three female Weimaraner pups had generalized and rhythmic body tremors since the first week of age. The remaining two male littermates were unaffected. One 4-week-old female was euthanatized and necropsied. On gross examination, poor demarcation between the gray and white matter was observed. Microscopically, there was severe hypomyelination of the brain compatible with congenital hypomyelinogenesis reported in dogs