22q11.2 Microduplications: Two Clinical Reports Compared with Similar Cases from the Literature

J Pediatr Genet. 2020 Sep;9(3):211-220. doi: 10.1055/s-0039-1700980. Epub 2020 Jan 10.

Abstract

We present two male subjects (6 and 14 years old) with mild dysmorphism, intellectual disability, and/or autism spectrum disorder with chromosome 22q11.2 microduplications of different sizes. We then compared the clinical and genetic findings with similar cases from the literature sharing the same 22q11.2 duplications. These rare duplications in our subjects were identified by high-resolution chromosomal microarray analysis and flanked by low copy repeats in the 22q11.2 region, specifically LCR22A, LCR22B, and LCR22D. The typical 22q11.2 defect generally involves a deletion at breakpoints LCR22A and LCR22D causing DiGeorge or velo-cardio-facial syndrome and not duplications of varying sizes as seen in our male subjects.

Keywords: 22q11.2 breakpoints at LCR22A, B, C, or D; 22q11.2 microduplications; literature reports; low copy repeats.

Publication types

  • Case Reports