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Epileptic encephalopathies (EE) include a range of severe epilepsies in which intractable seizures or severe sub-clinical epileptiform activity are accompanied by impairment of motor and cognitive functions. Mutations in several genes including ion channels and other genes whose function is not completely understood have been associated to some EE. In this report, we provide a detailed clinical description of a sporadic male patient with early-onset epilepsy and epileptic encephalopathy in whom we performed complete exome sequencing (WES) and identified a GRIN2B mutation. The GRIN2B splicing mutation in intron 10 (c.2011-1G>A) was revealed in a WES study. The result was confirmed by Sanger sequencing. No mutation was found in both parents. Our finding confirms that early-onset EE may be caused not only by gain-of-function variants but also by splice site mutations-in particular those affecting the splice acceptor site of the 10th intron of the GRIN2B gene. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Clinical manifestations of Jacobsen syndrome (JBS) depend on the size of the 11qter deletion, which usually varies between approximately 7 and 20 Mb. Typical JBS features include developmental delay/mental retardation, short stature, congenital heart defects, thrombocytopenia, and characteristic dysmorphic facial features. We report on a family in which a 4-year-old girl as well as her mother and maternal uncle present with subtle features of JBS. Notably, neither thrombocytopenia nor congenital anomalies were detected in this family. Cytogenetic analyses revealed normal karyotypes. Using fluorescence in situ hybridization (FISH) and whole-genome oligonucleotide array CGH analyses, we identified an approximately 5 Mb deletion of the terminal part of chromosome 11q in all the three affected family members. The deletion breakpoint was mapped between 129,511,419 and 129,519,794 bp. This is the smallest deletion reported in a JBS patient. Interestingly, the FLI1 (friend leukemia virus integration 1) hematopoiesis factor gene located approximately 6.5 Mb from 11qter and usually deleted in patients with JBS, is intact. Our data support previous hypotheses that FLI1 haploinsufficiency is responsible for thrombocytopenia in patients with JBS., (Copyright 2008 Wiley-Liss, Inc.)