A de novo chromosomal abnormality in Cri du Chat syndrome

To find the length and location of the deletions in the short arm of chromosome 5 in one case of Cri du Chat syndrome using oligo array comparative genomic hybridization.

Metaphase chromosomes were prepared from peripheral blood lymphocyte cultures using standard cytogenetic protocols. Chromosomal analysis was done in G-banded metaphases. Oligo array comparative genomic hybridization and fluorescence in situ hybridization were performed by the commercially available kits.

Oligonucleotide array comparative genomic hybridization (CGH) analysis revealed a 23.263 Mb deletion at region 5p14.2-->qter, combined with a duplication of 14.602 Mb in size in the area 12p13.1-->pter. Chromosomal aberrations were confirmed by fluorescence in situ hybridization. The male neonate with Cri du Chat syndrome had an unbalanced translocation which was inherited from his father who was a balanced carrier with a karyotype 46, XY, t (5; 12) (p14.2; p13.1).

This report shows the clinical utility of the oligonucleotide array in the detection of submicroscopic chromosomal aberrations, thus improving the molecular diagnosis of Cri du Chat syndrome.