Medical DevicesScientists Uncover Patterns Of Genetic Changes In Mental Retardation
Researchers at Radboud University Medical Centre, together with UK
Medical Research Council scientists at Oxford University, have uncovered
some of
the central characteristics of genes underlying mental retardation. The
research, which shortens the list of genes whose changes lead to this
disorder
from thousands to several dozen, is published June 26 in the open-access
journal PLoS Genetics.
Mental retardation, which affects approximately two percent of the
population, is often caused by many different, yet individually rare DNA
deletions
and duplications. Pinpointing the DNA changes responsible has proven
challenging precisely because these changes are not concentrated in a
small
number of genes.
The scientists took DNA from over 150 individuals with mental retardation
and compared it with descriptions of 5,000 mice whose genomes each had
single genes disrupted. The researchers found that the DNA changes
associated with mental retardation contained greater than expected
numbers of
genes whose loss in mice also affected the nervous system. The large
amounts of data from humans and mice were critical in revealing a
relatively
small set of genes that are relevant to mental retardation in humans.
This study provides strong evidence that genomic deletions and
duplications frequently cause mental retardation. By narrowing down the
list of genes
linked to the disorder, the research will help to enable genetic testing
and diagnosis. In the future, the approach used in this study could also
prove effective in highlighting genes altered in other medical conditions
such as schizophrenia and autism.
In some countries, including the UK, mental retardation is more properly referred to by clinicians as learning difficulty.
The following organisations provided funding for this work: UK Medical Research Council, Berrow Lord Florey scholarship,
the Swiss National Science Foundation, the Netherlands Organisation for
Health Research and Development, and the EU-sponsored AnEUploidy project. The
funders had no role in study design, data collection and analysis,
decision to publish, or preparation of the manuscript.
CITATION:
"Forging Links between Human Mental Retardation-Associated CNVs and Mouse Gene Knockout Models".
Webber C, Hehir-Kwa JY, Nguyen D-Q, de Vries BBA, Veltman JA, et al. (2009)
PLoS Genet 5(6): e1000531. doi:10.1371/journal.pgen.1000531
The Public Library of Science (PLoS)