Mental Retardation

Max Planck Institute for Molecular Genetics

home

contact

search

Human Molecular Genetics

Research Group Familial Cognitive Disorders

	X-linked mental retardation
	Autosomal recessive mental retardation
	Team
	Projects
	Collaborations
	Publications
	MRX Consortium
	German Mental Retardation Network (MRNET)

Projects

Large scale investigation of autosomal recessive mental retardation (ARMR) in consanguineous families:

Together with our collaboration partners from Iran, we are studying an increasing number of more than 200 large consanguineous families with at least two ARMR affected individuals per family. While our focus is on non-syndromic mental retardation cases (mentally retarded individuals who do not show major physical abnormalities, dysmorphism, or neurological abnormalities) we also investigate syndromic forms of ARMR.
Using SNP arrays, each individual is being genotyped for genome wide distributed genetic Markers. Genotyping results are susequently used for linkage analysis i.e. the identification of chromosomal regions that are cosegregating with the disease. The genes contained in the thus identified linkage intervals are then being screened for putative disease causing mutations. For mutation screening we are in many cases now employing state of the art genomic enrichment methods together with high throughput sequencing technologies (e.g. the Illumina Genome Analyzer).

Functional characterisation of mental retardation (MR) genes:

Once a cosegregating mutation is identified and excluded in a large panel of controls, we pursue investigations into functional properties of the affected genes. In this context are working together with or our national and international collaboration partners and apply various strategies and methods. One prominent approach is e.g. the application of array based gene expression profiling, which has been pioneered in the department (Sudbrak et al. 2001).

Array based resequencing of Candidate Genes for X-linked mental retardation (XLMR):

In the course of elucidating the molecular causes of non-syndromic XLMR more than 20 genes have been cloned. We now have generated a custom-designed resequencing chip based on the 50K Affymetrix CustomSeq Resequencing array platform. The array allows the coeval analysis of the coding regions and exon-intron junctions of 17 known XLMR-genes and will enable us to identify families harboring mutations in these genes. Here, the initial focus lies on families obtained through the European MRX Consortium. Furthermore, we are assessing the potential of the array as a tool in mental retardation diagnostics.