Clinical and molecular findings in nine new cases of tetrasomy 18p syndrome: FISH and array CGH characterization

Autor: Nesrine Jammali, Fatma-Zohra Chioukh, Sarra Dimassi, Molka Kammoun, Ali Saad, Hela Ben Khelifa, Hanene Hannachi, D Sanlaville, Soumaya Mougou-Zerelli, Wafa Slimani, Sarra Bouslah, Afef Jelloul
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Molecular Cytogenetics
Molecular Cytogenetics, Vol 12, Iss 1, Pp 1-7 (2019)
ISSN: 1755-8166
1476-3575
Popis: Background Small Supernumerary Marker Chromosomes (sSMC) are rare chromosomal abnormalities, which have abnormal banding arrangement and take many shapes. Several disorders have been correlated with sSMC presence. The aim of this study is to characterize the sSMC derived from chromosome 18 by Fluorescence in situ hybridization (FISH) and Array Comparative Genomic Hybridization (aCGH). Results Nine children with dysmorphic features have been investigated. They have these features in common: a triangular face, low-set ears, a large mouth with a thin upper lip, and a horizontal palpebral fissure. Epicanthus and strabismus were present in two patients. In addition, we have noticed microcephaly and mental and/or developmental delay with low birth weight. However, two patients had standard birth weight; one patient had hypospadias; two had skin problems; and three showed different congenital heart defects. One patient had corpus callosum hypoplasia. Systematic karyotype analysis revealed a de novo supernumerary chromosome. Array CGH showed a gain in copy number on the short arm of chromosome 18 in the nine cases. In one case, the sSMC seemed to be in mosaic. The breakpoints of the marker were identified using aCGH and FISH. Thus, the sSMC led to 18p tetrasomy with approximately 14 Mb lengths, between 364344 and 14763575 based on the human genome version 18. Conclusions These results have been completed by FISH in order to ascertain the shape of the sSMC. Our results confirm the uniqueness and particularity of the iso18p syndrome on the phenotypic as well as on the genetic level.
Databáze: OpenAIRE