title: Refinement of the deletion in 8q22.2-q22.3: the minimum deletion size at 8q22.3 related to intellectual disability and epilepsy.
abstract: Kuechler et al. [2011] reported five patients with interstitial deletions in 8q22.2-q22.3 who had intellectual disability, epilepsy, and dysmorphic features. We report on a new patient with the smallest overlapping de novo deletion in 8q22.3 and refined the phenotype. The proposita was an 8-year-old girl, who developed seizures at 10 months, and her epileptic seizure became severe and difficult to control with antiepileptic drugs. She also exhibited developmental delay and walked alone at 24 months. She was referred to us for evaluation for developmental delay and epilepsy at the age of 8 years. She had intellectual disability (IQ 37 at 7 years) and autistic behavior, and spoke two word sentences at 8 years. She had mild dysmorphic features, including telecanthus and thick vermilion of the lips. Array comparative genomic hybridization detected a 1.36 Mb deletion in 8q22.3 that encompassed RRM2B and NCALD, which encode the small subunit of p53-inducible ribonucleotide reductase and neurocalcin delta in the neuronal calcium sensor family of calcium-binding proteins, respectively. The minimum overlapping region between the present and previously reported patients is considered to be a critical region for the phenotype of the deletion in 8q22.3. We suggest that the deletion in 8q22.3 may represent a clinically recognizable condition, which is characterized by intellectual disability and epilepsy.
authors.affiliation: Division of Medical Genetics, Kanagawa Children's Medical Center, Yokohama, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Kuroda
authors.forename: Ikuko
authors.initials: I
authors.lastname: Ohashi
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Saito
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Nagai
authors.forename: Kazumi
authors.initials: K
authors.lastname: Ida
authors.forename: Takuya
authors.initials: T
authors.lastname: Naruto
authors.forename: Mizue
authors.initials: M
authors.lastname: Iai
authors.forename: Kenji
authors.initials: K
authors.lastname: Kurosawa
mesh_terms: D002648:Child; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D002898:Chromosomes, Human, Pair 8; D055028:Comparative Genomic Hybridization; D004827:Epilepsy / Q000175:diagnosis / Q000235:genetics*; D019066:Facies; D005260:Female; D056726:Genetic Association Studies; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008607:Intellectual Disability / Q000175:diagnosis / Q000235:genetics*; D010641:Phenotype
keywords: 8q22.3 deletion; NCALD; RRM2B; epilepsy; intellectual disability