Identification of genome-wide copy number variations and a family-based association study of Avellino corneal dystrophy

Ophthalmology. 2010 Jul;117(7):1306-12.e4. doi: 10.1016/j.ophtha.2009.11.021. Epub 2010 Mar 3.

Abstract

Objective: To determine the association of identified copy number variations (CNVs) in whole genome with the risk of Avellino corneal dystrophy (ACD) in a Korean population.

Design: Case-control study.

Participants: A total of 146 patients with ACD and 226 control subjects.

Methods: A total of 193 trios were genotyped by the Illumina HumanHapCNV370-Duo BeadChip (370,404 markers) (Illumina, Inc., San Diego, CA). The intensity signal (log R ratio) and allelic intensity ratio (B allele frequency) of each marker in all individuals were obtained by Illumina BeadStudio software (Illumina, Inc.). To obtain authentic CNVs in this study, we performed a family-based CNV validation and family-based boundary mapping using the PennCNV algorithm, which incorporates multiple factors, including total log R ratio, B allele frequency, and family information, based on an integrated hidden Markov model.

Main outcome measures: Statistical comparison and identification of CNVs between case and control using family information.

Results: We identified 27,267 individual trio CNVs with a median size of 16.2 kb, aggregated in 2245 CNV regions. Most of the identified trio CNVs in this study showed well-defined CNV boundaries and overlapped with those in the Database of Genomic Variants (DGV) (83.4% in number and 79.2% in length). With the common CNV regions (264 CNV regions >5%), we performed a family-based association test with the risk of ACD.

Conclusions: Two CNV regions (chr6:29978470-29987783 and chr14:59896944-59916129) were significantly associated with the risk of ACD (P=0.05-0.003 and P=0.008, respectively). This study describes the first results of a genome-wide association analysis of individual CNVs with the risk of ACD and shows that 2 novel CNV loci may be involved in the risk of ACD.

Financial disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Algorithms
  • Asian People / genetics
  • Case-Control Studies
  • Child
  • Child, Preschool
  • Corneal Dystrophies, Hereditary / genetics*
  • DNA Copy Number Variations*
  • Female
  • Genome, Human / genetics*
  • Genome-Wide Association Study*
  • Genotype
  • Humans
  • Korea / epidemiology
  • Male
  • Middle Aged
  • Polymorphism, Single Nucleotide / genetics
  • Risk Assessment