Detection of LOH of the RB1 gene in bladder cancers by PCR-RFLP.

OBJECTIVES: Retinoblastoma (RB1) gene involves in retinoblastoma, osteosarcoma, bladder, prostate, lung, breast carcinomas, and soft tissue sarcomas. Loss of heterozygosity (LOH) is the most common mutation of the gene. METHODS: Xba I polymorphism in intron 17 of the gene was used to detect LOH in 20 bladder cancer patients. A cystitis and an osteosarcoma were used as control. LOH was investigated in three different kinds of samples (blood, paraffin-embedded tissue and fresh tissue) belonging to the same patients, and 20 blood samples, 20 paraffin-embedded tissue samples and 16 fresh tissue samples were obtained from 20 cancer patients. RESULTS: None of the 20 blood samples showed LOH. Eleven out of 20 paraffin-embedded bladder tissues were amplified, 3 of them homozygous and all 8 informative paraffin-embedded tissues showed LOH. Five out of 16 fresh tumor tissues obtained were amplified, in 1 the fresh tissue was normal, 1 fresh tissue showed LOH and 3 were not digested by Xba I. CONCLUSION: The results of the study have suggested that detection of LOH of the RB1 gene by PCR-RFLP can be a good adjunctive test for evaluation of the bladder cancer

Abnormal brain cholesterol homeostasis in Alzheimer’s disease—a targeted metabolomic and transcriptomic study

The role of brain cholesterol metabolism in Alzheimer’s disease (AD) remains unclear. Peripheral and brain cholesterol levels are largely independent due to the impermeability of the blood brain barrier (BBB), highlighting the importance of studying the role of brain cholesterol homeostasis in AD. We first tested whether metabolite markers of brain cholesterol biosynthesis and catabolism were altered in AD and associated with AD pathology using linear mixed-effects models in two brain autopsy samples from the Baltimore Longitudinal Study of Aging (BLSA) and the Religious Orders Study (ROS). We next tested whether genetic regulators of brain cholesterol biosynthesis and catabolism were altered in AD using the ANOVA test in publicly available brain tissue transcriptomic datasets. Finally, using regional brain transcriptomic data, we performed genome-scale metabolic network modeling to assess alterations in cholesterol biosynthesis and catabolism reactions in AD. We show that AD is associated with pervasive abnormalities in cholesterol biosynthesis and catabolism. Using transcriptomic data from Parkinson’s disease (PD) brain tissue samples, we found that gene expression alterations identified in AD were not observed in PD, suggesting that these changes may be specific to AD. Our results suggest that reduced de novo cholesterol biosynthesis may occur in response to impaired enzymatic cholesterol catabolism and efflux to maintain brain cholesterol levels in AD. This is accompanied by the accumulation of nonenzymatically generated cytotoxic oxysterols. Our results set the stage for experimental studies to address whether abnormalities in cholesterol metabolism are plausible therapeutic targets in AD

UvA-DARE (Digital Academic Repository) Link to publication Citation for published version (APA): Evaluation of Complex Inheritance Involving the Most Common Bardet-Biedl Syndrome Locus (BBS1)

General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Download date: 02 Jul 2019 Am. J. Hum. Genet. 72:429-437, 2003 429 Bardet-Biedl syndrome (BBS) is a genetic disorder with the primary features of obesity, pigmentary retinopathy, polydactyly, renal malformations, mental retardation, and hypogenitalism. Patients with BBS are also at increased risk for diabetes mellitus, hypertension, and congenital heart disease. BBS is known to map to at least six loci: 11q13 (BBS1), 16q21 (BBS2), 3p13-p12 (BBS3), 15q22.3-q23 (BBS4), 2q31 (BBS5), and 20p12 (BBS6). Although these loci were all mapped on the basis of an autosomal recessive mode of inheritance, it has recently been suggested-on the basis of mutation analysis of the identified BBS2, BBS4, and BBS6 genes-that BBS displays a complex mode of inheritance in which, in some families, three mutations at two loci are necessary to manifest the disease phenotype. We recently identified BBS1, the gene most commonly involved in Bardet-Biedl syndrome. The identification of this gene allows for further evaluation of complex inheritance. In the present study we evaluate the involvement of the BBS1 gene in a cohort of 129 probands with BBS and report 10 novel BBS1 mutations. We demonstrate that a common BBS1 missense mutation accounts for ∼80% of all BBS1 mutations and is found on a similar genetic background across populations. We show that the BBS1 gene is highly conserved between mice and humans. Finally, we demonstrate that BBS1 is inherited in an autosomal recessive manner and is rarely, if ever, involved in complex inheritance. Evaluation of Complex Inheritance Involving the Most Common Bardet-Biedl Syndrome Locus (BBS1