Patient With Delayed Development Resulting From De Novo Duplication of 7q36.1-q36.3 and Deletion of 9p24.3

Abstract

Patients with a duplication from 7q36 to the terminus or a deletion of 9p24 have been reported, whereas those harboring both mutations have not. Here, we report a patient with simultaneous de novo 7q36.1-q36.3 duplication and 9p24.3 deletion. A 6-year-old boy presented with speech developmental delay, microcephaly, and dysmorphic features, including a long face and small nose. Chromosome and array comparative genomic hybridization analyses revealed 46,XY,dup(7)(q36.1-q36.3) and del(9)(p24.3). The sizes of the duplication and deletion were 9.9 Mb and 1.9 Mb, respectively. The duplication of chromosome 7 contained 68 known genes, of which 3 are related with entries in the Developmental Disorders Genotype-to-Phenotype (DDG2P) database. The deletion of chromosome 9 contained 6 known genes, of which 2 are in the DDG2P database. We investigated the genotype and phenotype in this patient, and reviewed the relevant literatures for possible clinical presentation in these variations.

Report of a patient with a de novo non-recurrent duplication of 17p11.2p12 and Yq11 deletion

“…His parents presented normal karyotypes and aCGH results, but no further effort was made to identify the parental origin of each alteration. Both 7q duplication and 9p deletion syndromes have been described, but they are heterogeneous and variable in the sizes of the alterations and their clinical manifestations [10].…”

“…To our knowledge, only two patients with concurrent de novo deletion/duplication events involving two chromosomes have been reported in the literature [9, 10]; neither case involved both chromosomes 17 and Y, and no pathophysiological mechanism was proposed in either report. Here, we present the first case report of a patient bearing two non-recurrent de novo rearrangements involving a 10.8-Mb duplication of 17p11.2p12 and a 14.7-Mb deletion of Yq11.…”

Identification of Microdeletion of 7q36.1-qter in Fetal Hemivertebrae with Scoliosis

“…Diagnosis basing on clinical symptoms of the deletion of the long arm of chromosome 7 (7qter) is more difficult than most other chromosomal abnormalities due to the wide related phenotype variations. Currently terminal deletions of 7 qter are well known and are frequently linked with holoprosencephaly or hypotelorism due to the involvement of the SHH gene located in 7q36.3 [3][4][5][6][7][8]. The typical clinical phenotypes of 7qter include congenital limb deformity (polysyndactyly), brain malformations, often with the holoprosencephaly spectrum, mental retardation and short stature [4,6,7,9].…”