When we worked on Down Syndrome brain in the past we have been focus ing on adult brain. This was a major step forwards as most work on Down Syndrome was carried out on fibroblasts or other tissues and, moreover, we introduced proteomics to identify and quantify brain protein expression. We considered evaluation of brain protein expression in Down Syndrome brain by and by more important than gene hunting at the nucleic acid level realiz ing the long unpredictable way from RNA to protein. The availability of fetal samples along with the proteomic appproach stimulated and reinforced studies on Down Syndrome brain. And indeed, it was found out that some observations on aberrant protein expression in adult Down Syndrome brain could not be verified in the fetal samples indi cating that neurodegeneration in adult Down Syndrome brain may have been responsible rather than trisomy 21. Using brains from the early second trimester of gestation led to the generation of a series of clues for the under standing of aberrant wiring of the brain in Down Syndrome and enabled the determination of altered key functions in early life; e. g. undetectably low drebrin was observed in Down Syndrome cortex, an integral constituent and marker for dendritic spines, main effectors of cross-talk between neurons. In addition, evaluation of the nature of the neuronal deficits in terms of neuro transmission markers could be established as well as neuronal density in fetal Down Syndrome cortex.

This book contains updated reviews and original research work on Down Syndrome focussing on brandnew results in neurobiology, in particular results on gene hunting (subtractive hybridization, differential display) and neurochemistry. The book provides new data such as a subtractive library of Down Syndrome brain showing cDNAs that are overexpressed or downregulated and can be regarded as a source for further research on the preliminary transcriptional data given. A 2D-electrophoretic map of human brain proteins including Down Syndrome brain protein expression established by in-gel-digestion of spots with subsequent MALDI-identification provides the scientific basis for protein work to the neuroscientist. Altogether, the book provides a series of new candidate genes possibly involved in Down Syndrome neurobiology, tools for neuroscience studies on Down Syndrome brain thus serving as a manual and updated views and aspects on Down Syndrome pathobiology.

Down syndrome (DS) is the most common example of neurogenetic aneuploid disorder leading to mental retardation. In most cases, DS results from an extra copy of chromosome 21 (HSA21) producing deregulated gene expression in brain that gives raise to subnormal intellectual functioning. The topic of this volume is of broad interest for the neuroscience community, because it tackles the concept of neurogenomics, that is, how the genome as a whole contributes to a neurodevelopmental cognitive disorders, such as DS, and thus to the development, structure and function of the nervous system. This volume of Progress in Brain Research discusses comparative genomics, gene expression atlases of the brain, network genetics, engineered mouse models and applications to human and mouse behavioral and cognitive phenotypes. It brings together scientists of diverse backgrounds, by facilitating the integration of research directed at different levels of biological organization, and by highlighting translational research and the application of the existing scientific knowledge to develop improved DS treatments and cures. Leading authors review the state-of-the-art in their field of investigation and provide their views and perspectives for future research Chapters are extensively referenced to provide readers with a comprehensive list of resources on the topics covered All chapters include comprehensive background information and are written in a clear form that is also accessible to the non-specialist

Genetics and Neurobiology of Down Syndrome provides a thorough review of the genetic etiology and mechanisms of trisomy 21. The author discusses the history of the syndrome, along with the clinical features and health consequences, including physical features, cognitive, and neurologic symptoms. Genetic counseling on pros and cons of prenatal screening and testing and associated ethical issues are explored. This unique book also covers the societal and demographic aspects as well as the future direction of therapeutic development. Reviews genetic etiology and mechanisms of trisomy 21 Discusses prenatal screening and genetic counseling, including ethical aspects Explores link between Down Syndrome and susceptibility to Alzheimer’s and early brain aging Covers cognitive and neurological symptoms and other health consequences Identifies future therapeutic developments

The Neurobiology of Aging and Alzheimer Disease in Down Syndrome provides a multidisciplinary approach to the understanding of aging and Alzheimer disease in Down syndrome that is synergistic and focused on efforts to understand the neurobiology as it pertains to interventions that will slow or prevent disease. The book provides detailed knowledge of key molecular aspects of aging and neurodegeneration in Down Syndrome by bringing together different models of the diseases and highlighting multiple techniques. Additionally, it includes case studies and coverage of neuroimaging, neuropathological and biomarker changes associated with these cohorts. This is a must-have resource for researchers who work with or study aging and Alzheimer disease either in the general population or in people with Down syndrome, for academic and general physicians who interact with sporadic dementia patients and need more information about Down syndrome, and for new investigators to the aging and Alzheimer/Down syndrome arena. - Discusses the complexities involved with aging and Alzheimer's disease in Down syndrome - Summarizes the neurobiology of aging that requires management in adults with DS and leads to healthier aging and better quality of life into old age - Serves as learning tool to orient researchers to the key challenges and offers insights to help establish critical areas of need for further research

"Advances in Down Syndrome Research” represents updated research in several areas of Down Syndrome (DS). A new promising animal model of DS is reported and this opens new opportunities to study pathomechanisms and pharmacological approaches as it is more than difficult to carry out studies in humans and the clinical features are highly variable. In terms of biology, cell cycle and stem cell studies and in terms of biochemistry, relevance of studies on a specific protein kinase, channels, transporters, superoxide dismutase, antioxidant system, chromosome assembly factor and other important biological structures are provided. And again, the gene dosage hypothesis is addressed and although the vast majority of chromosome 21 gene products is unchanged in fetal DS brain, a few specific chromosome 21 encoded structures including transcription factors are indeed overexpressed although findings in fetal DS are different from those in adult DS brain when Alzheimer-like neuropathology supervenes.

Research on the multiple aspects of cognitive impairment in Down syndrome (DS), from genes to behavior to treatment, has made tremendous progress in the last decade. The study of congenital intellectual disabilities such as DS is challenging since they originate from the earliest stages of development and both the acquisition of cognitive skills and neurodegenerative pathologies are cumulative. Comorbidities such as cardiac malformations, sleep apnea, diabetes and dementia are frequent in the DS population, as well, and their increased risk provides a means of assessing early stages of these pathologies that is relevant to the general population. Notably, persons with DS will develop the histopathology of Alzheimer’s disease (formation of neuritic plaques and tangles) and are at high risk for dementia, something that cannot be predicted in the population at large. Identification of the gene encoding the amyloid precursor protein, its localization to chromosome 21 in the 90’s and realization that all persons with DS develop pathology identified this as an important piece of the amyloid cascade hypothesis in Alzheimer’s disease. Awareness of the potential role of people with DS in understanding progression and treatment as well as identification of genetic risk factors and also protective factors for AD is reawakening. For the first time since DS was recognized, major pharmaceutical companies have entered the search for ameliorative treatments, and phase II clinical trials to improve learning and memory are in progress. Enriched environment, brain stimulation and alternative therapies are being tested while clinical assessment is improving, thus increasing the chances of success for therapeutic interventions. Researchers and clinicians are actively pursuing the possibility of prenatal treatments for many conditions, an area with a huge potential impact for developmental disorders such as DS. Our goal here is to present an overview of recent advances with an emphasis on behavioral and cognitive deficits and how these issues change through life in DS. The relevance of comorbidities to the end phenotypes described and relevance of pharmacological targets and possible treatments will be considerations throughout.