Chromosomal Deletion Syndromes: Common Types, Causes and Detection Methods
1 Anđela Strujić
1 Ivna Kocijan
1 University of Applied Health Sciences, Zagreb
Chromosomes are structures composed of a DNA molecule and histone proteins that carry genetic information. They are located in the cell nucleus and become visible under light microscope during cell division. A karyogram is used to depict the number and structure of chromosomes, whereby a normal human karyogram has 46 chromosomes arranged in 23 homologous pairs. Changes in the number or structure of chromosomes lead to various genetic conditions and syndromes. Chromosomal deletions represent one of the most severe forms of chromosomal aberrations as they involve the loss of genetic material, causing severe disorders such as cri-du-chat, Wolf-Hirschhorn, Prader-Willi and Angelman syndromes. Prenatal diagnostic methods are used to check fetal growth and development and determine a type of fetal abnormality, if present, with commonly performed procedures including ultrasound, amniocentesis, chorionic villus sampling and cordocentesis. Final diagnosis is established through laboratory methods such as karyotyping, fluorescence in situ hybridization and chromosomal microarray analysis.
Keywords: chromosome, deletion, syndrome, prenatal diagnostics, laboratory diagnostics