RESUMEN
In the present study we analysed the genotype of HFE, the gene involved in hemochromatosis, in 107 patients with sporadic late-onset AD and in 99 age-matched non-demented controls. We observed that patients carrying the mutant HFE-H63D allele had a mean age at onset of 71.7 +/- 6.0 years versus 76.6 +/- 5.8 years of those who were homozygous for the wild-type allele (p = 0.001). The frequency of the HFE-H63D mutation was highest (0.22) in the patients aged <70 years at the time of disease onset, whereas it was 0.12 in those with disease onset at an age of 70-80 years, and 0.04 in those aged more than 80 years. The APOE genotype did not significantly modify the effect of HFE on age at onset. We conclude that mild disturbances of iron homeostasis associated with a common genetic determinant may interact with other pathogenic mechanisms involved in AD. HFE mutations may anticipate AD clinical presentation in susceptible individuals.
Asunto(s)
Enfermedad de Alzheimer/genética , Antígenos HLA/genética , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Proteínas de la Membrana , Edad de Inicio , Anciano , Anciano de 80 o más Años , Apolipoproteína E4 , Apolipoproteínas E/genética , Femenino , Frecuencia de los Genes , Genotipo , Proteína de la Hemocromatosis , Humanos , Masculino , Persona de Mediana Edad , Mutación , Factores de RiesgoRESUMEN
Differences in neuropsychological performance associated with specific test presentation sequences have been reported in adults. However, these effects have received little attention in children. The EOWPVT-R, a measure of one-word expressive language, and the PPVT-R, a measure of receptive language, were administered to 6- to 14-year-olds (control [n = 17] and experimental [n = 22] groups) in a counterbalanced fashion to investigate the potential effects of test presentation sequence on neuropsychological performance. Group findings were not evidenced subsequent to variation in test administration sequence. In contrast, order of test presentation revealed differences in performance. Administration of the PPVT-R prior to the EOWPVT-R resulted in enhanced EOWPVT-R expressive language scores in both groups of participants. Presentation of the PPVT-R after the EOWPVT-R did not affect performance. Applied and theoretical implications associated with these findings are discussed.
