title: Disruption of EXOC6B in a patient with developmental delay, epilepsy, and a de novo balanced t(2;8) translocation.
abstract: Most balanced chromosomal aberrations are not associated with a clinical phenotype, however, in some patients they may disrupt gene structure. With the development of various next-generation sequencing techniques, fast and specific analyses of the breakpoint regions of chromosomal rearrangements are possible. Here, we report on a 19-year-old woman with a de novo balanced translocation t(2;8)(p13.2;q22.1) and a severe clinical phenotype including intellectual disability, epilepsy, behavioral features resembling autism, and minor dysmorphic features. By next-generation sequencing, we defined the breakpoints and found disruption of the exocyst complex component 6B (EXOC6B) gene in intron 1 on chromosome 2p13.2 involving two Alu elements with a homology of 81%. No gene was found at the respective breakpoint on chromosome 8. Expression analysis of the EXOC6B in blood lymphocytes and buccal smear revealed reduced expression in the patient in comparison with the control. Our findings in combination with one recently published case and one other patient listed in DECIPHER v5.1 indicate EXOC6B as a gene relevant for intellectual development and electrophysiological stability.
authors: Division of Human Genetics, Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, Innsbruck, Austria.
authors: Anne
authors: A
authors: Frühmesser
authors: Jonathon
authors: J
authors: Blake
authors: Edda
authors: E
authors: Haberlandt
authors: Bianka
authors: B
authors: Baying
authors: Benjamin
authors: B
authors: Raeder
authors: Heiko
authors: H
authors: Runz
authors: Ana
authors: A
authors: Spreiz
authors: Christine
authors: C
authors: Fauth
authors: Vladimir
authors: V
authors: Benes
authors: Gerd
authors: G
authors: Utermann
authors: Johannes
authors: J
authors: Zschocke
authors: Dieter
authors: D
authors: Kotzot
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics* / Q000378:metabolism; D056905:Chromosome Breakpoints; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics; D002898:Chromosomes, Human, Pair 8 / Q000235:genetics; D002658:Developmental Disabilities / Q000235:genetics* / Q000378:metabolism; D004827:Epilepsy / Q000235:genetics* / Q000378:metabolism; D005260:Female; D019204:GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism; D009061:Mouth Mucosa / Q000378:metabolism; D013577:Syndrome; D014178:Translocation, Genetic; D055815:Young Adult
chemical_list: C489222:EXOC6B protein, human; D019204:GTP-Binding Proteins