7q11.23 Duplications

Synonyms

Williams-Beuren region duplication

Definition

7q11.23 duplications are copy number variations (CNVs) in which an extra copy of 1,400 kb of DNA from the long arm of chromosome 7 is present. Duplications in this region are associated with “non-syndromic” ASD (Sanders et al. 2011). The region contains 26 genes, listed below, and is flanked by two segmental duplications (stretches of near-identical DNA). These are known to increase the likelihood of a process known as nonhomologous allelic recombination, which can lead to gains or losses of the chromosomal segment flanked by these repeats and account for the common breakpoints seen in the vast majority of individuals carrying duplications in this region. 7q11.23 duplications have also been seen in combination with intellectual disability, speech delay, and cardiac malformations (http://www.omim.org/entry/609757?search=7q11.23&highlight=7q1123).

Reciprocal deletions at 7q11.23 cause Williams-Beuren syndrome characterized by...