Distal 22q11.2 microduplication combined with typical 22q11.2 proximal deletion: a case report.
The 22q11 chromosomal region contains low copy repeats (LCRs) sequences that mediate non-allelic homologous recombination, which predisposes to copy number variations (CNVs) at this locus. Hemizygous deletions of the proximal 22q11.2 region result in the 22q11.2 deletion syndrome (22q11.2 DS). In addition, 22q11.2 duplications involving the distal LCR22s have been reported. This article describes a patient presenting a 2.5-Mb de novo deletion at proximal 22q11.21 region (between LCRs A-D), combined with a 1.3-Mb maternally inherited duplication at distal 22q11.23 region (between LCRs F-H). The presence of concomitant chromosomal imbalances found in this patient has not been reported previously. Clinical and molecular data were compared with literature, in order to contribute to genotype-phenotype correlation. These findings exemplify the complexity and genetic heterogeneity observed in 22q11.2 deletion syndrome and highlights the difficulty to make genetic counseling and predict phenotypic consequences in these situations.
['Molck|Miriam Coelho|MC|', 'Vieira|Társis Paiva|TP|', 'Simioni|Milena|M|', 'Sgardioli|Ilária Cristina|IC|', 'dos Santos|Ana Paula|AP|', 'Xavier|Ana Carolina|AC|', 'Gil-da-Silva-Lopes|Vera Lúcia|VL|']
D000015:Abnormalities, Multiple D000328:Adult D002648:Child D058674:Chromosome Duplication D002892:Chromosomes, Human, Pair 22 D004062:DiGeorge Syndrome D019066:Facies D005260:Female D056726:Genetic Association Studies D006801:Humans D008297:Male
copy number variations 22q11.2 deletion genotype-phenotype correlation 22q11.2 distal duplication