Mechanism of intrachromosomal triplications 15q11-q13: a new clinical report

Am J Med Genet A. 2003 Apr 30;118A(3):229-34. doi: 10.1002/ajmg.a.10164.

Abstract

We describe here a patient with intrachromosomal triplication 15q11-q13, a rare chromosomal event associated with severe mental retardation and intractable epilepsy. Cytogenetic studies including FISH on interphasic nuclei showed that the middle segment of the triplication was inverted in orientation. Molecular analyses demonstrated that the rearrangement was of maternal origin. Based on these cytogenetic and molecular data and those of the nine cases reported in the literature, we discuss the mechanistic origins of these triplications. We present several arguments for the mechanism involving two U-type exchanges occurring simultaneously at the pachytene stage of meiosis.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Cell Nucleus / ultrastructure
  • Chromosome Mapping
  • Chromosomes, Human, Pair 15*
  • Cytogenetics
  • Epilepsy / genetics*
  • Family Health
  • Female
  • Gene Duplication*
  • Genetic Markers
  • Humans
  • In Situ Hybridization, Fluorescence
  • Intellectual Disability / genetics*
  • Male
  • Meiosis
  • Models, Genetic
  • Pedigree

Substances

  • Genetic Markers