http://repub.eur.nl/res/aut/21263/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/35976/ 2007-02-01T00:00:00Z Mutations in the CSB gene cause Cockayne syndrome (CS), a DNA repair disorder characterized by UV sensitivity and severe physical and neurological impairment. CSB functions in the transcription-coupled repair subpathway of nucleotide excision repair. This function may explain the UV sensitivity but hardly clarifies the other CS symptoms. Many of these, including retinopathy, are associated with premature aging. We studied eye pathology in a mouse model for CS. Csbm/mmice were hypersensitive to UV light and developed epithelial hyperplasia and squamous cell carcinomas in the cornea, which underscores the importance of transcription-coupled repair of photolesions in the mouse. In addition, we observed a spontaneous loss of retinal photoreceptor cells with age in the Csbm/mretina, resulting in a 60% decrease in the number of rods by the age of 18 months. Importantly, when Csbm/mmice (as well as Csa-/-mice) were exposed to 10 Gy of ionizing radiation, we noticed an increase in apoptotic photoreceptor cells, which was not observed in wild-type animals. This finding, together with our observation that the expression of established oxidative stress marker genes is upregulated in the Csbm/mretina, suggests that (endogenous) oxidative DNA lesions play a role in this CS-specific premature-aging feature and supports the oxidative DNA damage theory of aging. Copyright http://repub.eur.nl/res/pub/5876/ 2001-11-02T00:00:00Z We investigated the risk associated with the codon 129 polymorphism in the prion protein gene (PRNP) and apolipoprotein E gene (APOE) isoforms for development of Creutzfeldt-Jakob disease (CJD) (n=126) and the possible influences on the disease pathology and its most important clinical characteristics. The PRNP M129V (PRNP129) polymorphism was determined using both DNA extracted from formalin fixed and paraffin embedded brain tissue (n=59) and leukocyte extracted DNA (n=67). In the latter group also the PRNP open reading frame and the APOE genotype were analysed and compared to a neurologically unaffected, age and sex matched control group (n=79). We found that methionine homozygosity of the PRNP129 increases the risk for developing CJD. PRNP129 also influenced the prion accumulation patterns in brain. The APOE 4 allele was an independent risk factor for developing CJD. We further observed a significant dose dependent APOE 4 effect on the number and type of amyloid-beta plaques in the brain of CJD patients.