Further delineation of Pitt-Hopkins syndrome: phenotypic and genotypic description of 16 novel patients

Institute of Human Genetics, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany.
Journal of Medical Genetics (Impact Factor: 5.64). 09/2008; 45(11):738-44. DOI: 10.1136/jmg.2008.060129
Source: PubMed

ABSTRACT Haploinsufficiency of the gene encoding for transcription factor 4 (TCF4) was recently identified as the underlying cause of Pitt-Hopkins syndrome (PTHS), an underdiagnosed mental-retardation syndrome characterised by a distinct facial gestalt, breathing anomalies and severe mental retardation.
TCF4 mutational analysis was performed in 117 patients with PTHS-like features.
In total, 16 novel mutations were identified. All of these proven patients were severely mentally retarded and showed a distinct facial gestalt. In addition, 56% had breathing anomalies, 56% had microcephaly, 38% had seizures and 44% had MRI anomalies.
This study provides further evidence of the mutational and clinical spectrum of PTHS and confirms its important role in the differential diagnosis of severe mental retardation.

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