Whole exome sequencing is an efficient, sensitive and specific method for determining the genetic cause of short-rib thoracic dystrophies

Clin Genet. 2015 Dec;88(6):550-7. doi: 10.1111/cge.12550. Epub 2015 Feb 17.

Abstract

Short-rib thoracic dystrophies (SRTDs) are congenital disorders due to defects in primary cilium function. SRTDs are recessively inherited with mutations identified in 14 genes to date (comprising 398 exons). Conventional mutation detection (usually by iterative Sanger sequencing) is inefficient and expensive, and often not undertaken. Whole exome massive parallel sequencing has been used to identify new genes for SRTD (WDR34, WDR60 and IFT172); however, the clinical utility of whole exome sequencing (WES) has not been established. WES was performed in 11 individuals with SRTDs. Compound heterozygous or homozygous mutations were identified in six confirmed SRTD genes in 10 individuals (IFT172, DYNC2H1, TTC21B, WDR60, WDR34 and NEK1), giving overall sensitivity of 90.9%. WES data from 993 unaffected individuals sequenced using similar technology showed two individuals with rare (minor allele frequency <0.005) compound heterozygous variants of unknown significance in SRTD genes (specificity >99%). Costs for consumables, laboratory processing and bioinformatic analysis were <AU$850 per sample. WES is sensitive, specific, efficient and cost-effective for mutation screening as well as gene discovery in SRTDs and can be considered a first-line methodology for mutation identification in affected individuals.

Keywords: Jeune syndrome; ciliopathy; exome sequencing; primary cilia; short-rib polydactyly.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / diagnosis
  • Abnormalities, Multiple / genetics*
  • Adaptor Proteins, Signal Transducing / genetics
  • Adult
  • Carrier Proteins / genetics
  • Cell Cycle Proteins / genetics
  • Child
  • Child, Preschool
  • Cytoplasmic Dyneins / genetics
  • Cytoskeletal Proteins
  • Exome / genetics*
  • Genetic Predisposition to Disease / genetics*
  • Genotype
  • Humans
  • Infant, Newborn
  • Microtubule-Associated Proteins / genetics
  • Mutation*
  • NIMA-Related Kinase 1
  • Protein Serine-Threonine Kinases / genetics
  • Reproducibility of Results
  • Ribs / abnormalities*
  • Sensitivity and Specificity
  • Sequence Analysis, DNA / methods*
  • Thorax / pathology*

Substances

  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • Cell Cycle Proteins
  • Cytoskeletal Proteins
  • DYNC2H1 protein, human
  • IFT172 protein, human
  • Microtubule-Associated Proteins
  • TTC21B protein, human
  • WDR34 protein, human
  • WDR60 protein, human
  • NEK1 protein, human
  • NIMA-Related Kinase 1
  • Protein Serine-Threonine Kinases
  • Cytoplasmic Dyneins