A 1.6-Mb microdeletion in chromosome 17q22 leads to NOG-related symphalangism spectrum disorder without intellectual disability

PLoS One. 2015 Mar 27;10(3):e0120816. doi: 10.1371/journal.pone.0120816. eCollection 2015.

Abstract

Microdeletions in chromosome 17q22, where the NOG gene resides, have been reported leading to the NOG-related symphalangism spectrum disorder (NOG-SSD), intellectual disability and other developmental abnormalities. In this study we reported a dominant Chinese Han family segregating with typical NOG-SSD symptoms including proximal symphalangism, conductive hearing loss, amblyopia and strabismus, but not intellectual disability. Sanger sequencing identified no pathogenic mutation in the coding regions of candidate genes NOG, GDF5 and FGF9. SNP genotyping in the genomic region surrounding NOG identified loss of heterozygosity in the affected family members. By array comparative genomic hybridization and quantitative real-time polymerase chain reaction, we identified and mapped the breakpoints of a novel 1.6-Mb microdeletion in chromosome 17q22 that included NOG and twelve other genes. It is the first microdeletion reported in chromosome 17q22 that is associated with NOG-SSD only but not with intellectual disability. Our results may help identifying the dosage sensitive genes for intellectual disability and other developmental abnormalities in chromosome 17q22. Our study also suggested that genomic deletions in chromosome 17q22 should be screened in the NOG-SSD patients in which no pathogenic mutation is identified by conventional sequencing methods.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / genetics*
  • Adult
  • Carpal Bones / abnormalities*
  • Child
  • Chromosome Deletion*
  • Chromosomes, Human, Pair 17 / genetics*
  • Comparative Genomic Hybridization / methods
  • Female
  • Foot Deformities, Congenital / genetics*
  • Genotype
  • Hand Deformities, Congenital / genetics*
  • Heterozygote
  • Humans
  • Intellectual Disability / genetics*
  • Male
  • Mutation / genetics*
  • Pedigree
  • Phenotype
  • Real-Time Polymerase Chain Reaction
  • Stapes / abnormalities*
  • Synostosis / genetics*
  • Tarsal Bones / abnormalities*

Supplementary concepts

  • NOG-Related-Symphalangism Spectrum Disorder

Grants and funding

This research was supported by grants from National Science Foundation of China (81222010 and 81371101 to TY), National Basic Research Program of China (2011CB504501 to HW), Minister of Science and Technology of China (2012BAI09B02 to HW), Shanghai Municipal Science and Technology Commission (14DZ2260300 and 14DJ1400201 to HW, 15YF1407600 to YC), Specialized Research Fund for the Doctoral Program of Higher Education (20130073110011 to TY) and Program for New Century Excellent Talents in University (NCET-13-0376 to TY). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.