Autosomal-dominant microtia linked to five tandem copies of a copy-number-variable region at chromosome 4p16

Am J Hum Genet. 2008 Jan;82(1):181-7. doi: 10.1016/j.ajhg.2007.08.001.

Abstract

Recently, large-scale benign copy-number variations (CNVs)--encompassing over 12% of the genome and containing genes considered to be dosage tolerant for human development--were uncovered in the human population. Here we present a family with a novel autosomal-dominantly inherited syndrome characterized by microtia, eye coloboma, and imperforation of the nasolacrimal duct. This phenotype is linked to a cytogenetically visible alteration at 4pter consisting of five copies of a copy-number-variable region, encompassing a low-copy repeat (LCR)-rich sequence. We demonstrate that the approximately 750 kb amplicon occurs in exact tandem copies. This is the first example of an amplified CNV associated with a Mendelian disorder, a discovery that implies that genome screens for genetic disorders should include the analysis of so-called benign CNVs and LCRs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / genetics*
  • Abnormalities, Multiple / pathology
  • Chromosomes, Human, Pair 4*
  • Coloboma / genetics
  • Coloboma / pathology
  • Ear, External / abnormalities*
  • Female
  • Gene Dosage*
  • Genes, Dominant*
  • Humans
  • Male
  • Nasolacrimal Duct / abnormalities
  • Pedigree
  • Syndrome