7p22.2 Microduplication: A Pathogenic CNV?

Partial duplication of the short arm of chromosome 7 is a rare chromosome rearrangement. The phenotype spectrum associated with this rearrangement is extremely variable even if in the last decade the use of high-resolution microarray technology for the investigation of patients carrying this rearrangement allowed for the identification of the 7p22.1 sub-band causative of this phenotype and to recognize the corresponding 7p22.1 microduplication syndrome. We report two unrelated patients that carry a microduplication involving the 7.22.2 sub-band. Unlike 7p22.1 microduplication carriers, both patients only show a neurodevelopmental disorder without malformations. We better characterized the clinical pictures of these two patients providing insight into the clinical phenotype associated with the microduplication of the 7p22.2 sub-band and support for a possible role of this sub-band in the 7p22 microduplication syndrome.

A 46,XY Female with a 9p24.3p24.1 Deletion and a 8q24.11q24.3 Duplication: A Case Report and Review of the Literature.

Deletion of distal 9p is associated with a rare clinical condition characterized by dysmorphic features, developmental delay, and ambiguous genitalia. The phenotype shows variable expressivity and is related to the size of the deletion. 8q24 duplication has been reported in only few cases to date, all showing dysmorphic features and mild psychomotor developmental delay. A case of chromosomal aberration involving a 9p terminal deletion with an 8q duplication has never been reported. Here, we describe a child with a female phenotype, male karyotype, dysmorphic features, ambiguous genitalia, and developmental delay. In order to assess the cause of the patient's phenotype, conventional karyotyping, FISH, and a chromosomal microarray analysis were performed on the patient and her parents. The cytogenetic and molecular analysis revealed an unbalanced chromosomal aberration with a duplication in the long arm of chromosome 8 at 8q24.11q24.3 associated with a distal deletion in the short arm of chromosome 9 at 9p24.3p24.1, derived from a maternal balanced translocation. We compared the clinical picture of our patient with other similar cases reported in the literature and found that some clinical findings, such as strabismus, symphalangism of the first finger, and cubitus valgus, have never been previously associated with 9p deletion or 8q duplication expanding the phenotypic range of this condition. This study is aimed to better define the clinical history and prognosis of patients with this rare chromosomal aberration.