Tjitske Kleefstra

TL;DR: De novo mutations represent an important cause of intellectual disability; exome sequencing was used as an effective diagnostic strategy for their detection.

TL;DR: Two de novo mutations--a nonsense mutation and a frameshift mutation--in the EHMT1 gene in patients with a typical 9q- phenotype are identified, establishing that haploinsufficiency of EH MT1 is causative for 9q subtelomeric deletion syndrome.

TL;DR: In this article, the coding regions of more than 21,000 genes obtained from 100 patients with an IQ below 50 and their unaffected parents were sequenced and a data-analysis procedure was developed to identify and classify de novo, autosomal recessive, and X-linked mutations.

TL;DR: A chromatin-modification module that underlies a recognizable form of ID, the Kleefstra syndrome phenotypic spectrum (KSS), is identified and a highly conserved epigenetic network that underlie cognition in health and disease is proposed.

TL;DR: The authors confirm the EHMT1 gene to be the major determinant of the 9qSTDS phenotype and Interestingly, five of six patients who had reached adulthood had developed severe psychiatric pathology, which may indicate that EH MT1 haploinsufficiency is associated with neurodegeneration in addition to neurodevelopmental defect.