Chromosomal Deletions

A chromosomal deletion is an abnormality in a chromosome where a segment of the chromosome is missing or deleted. These deletions vary in size and can be anywhere from a single DNA base pair to a sizeable segment of a chromosome. Chromosomal deletions can cause a wide range of medical conditions, including birth defects, developmental disabilities and even cancer. In some cases, the deleted genetic material alters how the gene works, resulting in a change in phenotype, while in other cases the deleted material is necessary for the gene to function properly. Detection and analysis of chromosomal deletions can be accomplished through a variety of methods such as cytogenetic analysis, fluorescence in situ hybridization (FISH) and array-based comparative genomic hybridization (array CGH). Chromosomal deletions can provide important information about the normal or abnormal functioning of an organism and can help to diagnose and treat various diseases and disorders.