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Xq28 duplications encompassing MECP2 have been described in male patients with a severe neurodevelopmental disorder associated with hypotonia and spasticity, severe learning disability and recurrent pneumonia. We identified an Xq28 duplication in three families where several male patients had presented with intestinal pseudo-obstruction or bladder distension. The affected boys had similar dysmorphic facial appearances. Subsequently, we ascertained seven further families where the proband presented with similar features. We demonstrated duplications of the Xq28 region in five of these additional families. In addition to MECP2, these duplications encompassed several other genes already known to be associated with diseases including SLC6A8, L1CAM and Filamin A (FLNA). The two remaining families were shown to have intragenic duplications of FLNA only. We discuss which elements of the Xq28 duplication phenotype may be associated with the various genes in the duplication. We propose that duplication of FLNA may contribute to the bowel and bladder phenotype seen in these seven families.European Journal of Human Genetics (2009) 17, 434–443; doi:10.1038/ejhg.2008.192; published online 15 October 2008 [ABSTRACT FROM AUTHOR]

We report the identification of six patients with 3q29 microdeletion syndrome. The clinical phenotype is variable despite an almost identical deletion size. The phenotype includes mild-to-moderate mental retardation, with only slightly dysmorphic facial features that are similar in most patients: a long and narrow face, short philtrum, and high nasal bridge. Autism, gait ataxia, chest-wall deformity, and long and tapering fingers were noted in at least two of six patients. Additional features—including microcephaly, cleft lip and palate, horseshoe kidney and hypospadias, ligamentous laxity, recurrent middle ear infections, and abnormal pigmentation—were observed, but each feature was only found once, in a single patient. The microdeletion is ∼1.5 Mb in length, with molecular boundaries mapping within the same or adjacent bacterial artificial chromosome (BAC) clones at either end of the deletion in all patients. The deletion encompasses 22 genes, including PAK2 and DLG1, which are autosomal homologues of two known X-linked mental retardation genes, PAK3 and DLG3. The presence of two nearly identical low-copy repeat sequences in BAC clones on each side of the deletion breakpoint suggests that nonallelic homologous recombination is the likely mechanism of disease causation in this syndrome. [ABSTRACT FROM AUTHOR]