title: Evolutionarily conserved low copy repeats (LCRs) in 22q11 mediate deletions, duplications, translocations, and genomic instability: an update and literature review.
abstract: Several constitutional rearrangements, including deletions, duplications, and translocations, are associated with 22q11.2. These rearrangements give rise to a variety of genomic disorders, including DiGeorge, velocardiofacial, and conotruncal anomaly face syndromes (DGS/VCFS/CAFS), cat eye syndrome (CES), and the supernumerary der(22)t(11;22) syndrome associated with the recurrent t(11;22). Chromosome 22-specific duplications or low copy repeats (LCRs) have been directly implicated in the chromosomal rearrangements associated with 22q11.2. Extensive sequence analysis of the different copies of 22q11 LCRs suggests a complex organization. Examination of their evolutionary origin suggests that the duplications in 22q11.2 may predate the divergence of New World monkeys 40 million years ago. Based on the current data, a number of models are proposed to explain the LCR-mediated constitutional rearrangements of 22q11.2.
authors.affiliation: Division of Human Genetics and Molecular Biology, The Children's Hospital of Philadelphia, Pennsylvania 19104, USA.
authors.forename: T H
authors.initials: TH
authors.lastname: Shaikh
authors.forename: H
authors.initials: H
authors.lastname: Kurahashi
authors.forename: B S
authors.initials: BS
authors.lastname: Emanuel
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics; D000818:Animals; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22; D005784:Gene Amplification; D017353:Gene Deletion; D018628:Gene Dosage; D020440:Gene Duplication; D006801:Humans; D008957:Models, Genetic; D010802:Phylogeny; D012091:Repetitive Sequences, Nucleic Acid; D013577:Syndrome; D014178:Translocation, Genetic