"Mental retardation (MR) is a highly heterogeneous disorder and is of genetic origin in about 50% of the cases. Despite recent progress in research the causes and the pathophysiology of MR remains obscure. It is essential to investigate this in order to develop future diagnostic and therapeutic strategies. The overall goal of this proposal is to establish an interdisciplinary Eastern Europe and Central Asia (EECA) consortium of experts with a joint programme of activities to generate knowledge about MR and the structure and dynamics of the brain as such. This project will be the first to study in depth the prevalence and incidence of MR in EECA . The objectives of the CHERISH project are to: - to develop a standardized approach for MR diagnosis through clinical workshops and courses - to create a large data-base of patients with clinically well defined MR, both syndromic and non-syndromic - identify cryptic genomic rearrangements through molecular cytogenetic analysis - sequence MR genes and analyse the molecular epidemiology of MR in Eastern European populations - develop diagnostic tools for recurrent/common mutations - identify new MR genes in X-linked and autosomal recessive forms of the disorder - increase awareness on the possible genetic origin of MR and implications for novel therapeutic strategies The project partners will join forces to create a large collection of samples and a database from MR patients which will be become the reference. All institutions involved are the referral centres for MR in their respective countries. The molecular studies will be performed in technologically-advanced genetic laboratories. A straightforward outcome of CHERISH will lay the basis for a significant improvement of clinical, educational and industrial developments. The project will contribute to improve the management of MR with the potential to reduce the high health care costs and to improve quality of life of the concerned population."