Isolated chromosome 8p23.2‑pter deletion: Novel evidence for developmental delay, intellectual disability, microcephaly and neurobehavioral disorders

Mol Med Rep. 2017 Nov;16(5):6837-6845. doi: 10.3892/mmr.2017.7438. Epub 2017 Sep 7.

Abstract

The current study presents a patient carrying a de novo ~6 Mb deletion of the isolated chromosome 8p23.2‑pter that was identified with a single‑nucleotide polymorphism array. The patient was characterized by developmental delay (DD)/intellectual disability (ID), microcephaly, autism spectrum disorder, attention‑deficit/hyperactivity disorders and mildly dysmorphic features. The location, size and gene content of the deletion observed in this patient were compared with those in 7 patients with isolated 8p23.2 to 8pter deletions reported in previous studies (4 patients) or recorded in the Database of Chromosomal Imbalance and Phenotype in Humans Using Ensembl Resources (DECIPHER) database (3 patients). The deletions reported in previous studies were assessed using a chromosomal microarray analysis. The 8p23.2‑pter deletion was a distinct microdeletion syndrome, as similar phenotypes were observed in patients with this deletion. Furthermore, following a detailed review of the potential associations between the genes located from 8p23.2 to 8pter and their clinical significance, it was hypothesized that DLG associated protein 2, ceroid‑lipofuscinosis neuronal 8, Rho guanine nucleotide exchange factor 10 and CUB and sushi multiple domains 1 may be candidate genes for DD/ID, microcephaly and neurobehavioral disorders. However, firm evidence should be accumulated from high‑resolution studies of patients with small, isolated, overlapping and interstitial deletions involving the region from 8p23.2 to 8pter. These studies will allow determination of genotype‑phenotype associations for the specific genes crucial to 8p23.2‑pter.

Publication types

  • Case Reports

MeSH terms

  • Child, Preschool
  • Chromosome Deletion
  • Chromosomes, Human, Pair 8*
  • Cytogenetic Analysis
  • Developmental Disabilities / diagnosis*
  • Developmental Disabilities / genetics
  • Genetic Association Studies
  • Humans
  • In Situ Hybridization, Fluorescence
  • Intellectual Disability / diagnosis*
  • Intellectual Disability / genetics
  • Karyotype
  • Male
  • Membrane Proteins / genetics
  • Microcephaly / diagnosis*
  • Microcephaly / genetics
  • Nerve Tissue Proteins / genetics
  • Neurodevelopmental Disorders / diagnosis*
  • Neurodevelopmental Disorders / genetics
  • Rho Guanine Nucleotide Exchange Factors / genetics

Substances

  • ARHGEF10 protein, human
  • CLN8 protein, human
  • DLGAP2 protein, human
  • Membrane Proteins
  • Nerve Tissue Proteins
  • Rho Guanine Nucleotide Exchange Factors