Deletion (genetics) - Wikipedia Small deletions are less likely to be fatal; large deletions are usually fatal – there are always variations based on which genes are lost Some medium-sized deletions lead to recognizable human disorders, e g Williams syndrome
Chromosomal Deletion Syndromes - The Merck Manuals These deletions may be visible on karyotyping but may sometimes be small and submicroscopic and occur just before the repetitive telometric sequences at either end of a chromosome
Conditions Caused by Deletion Mutations: Examples Diseases Chemicals such as alkylating agents, which are often used in chemotherapy to treat cancer, can cause deletions by adding alkyl groups to the DNA molecule Ionizing radiation, such as X-rays or UV radiation, can cause DNA damage and result in deletions
What Is a Deletion Mutation and How Does It Work? Errors in DNA repair mechanisms also contribute to deletions Cells have systems to correct DNA damage, but if these repair pathways fail to fix an error, a deletion can become permanent
Deletions and microdeletions — Knowledge Hub - GeNotes Deletions and microdeletions are a type of copy number variant that arise when regions of the genome are deleted The clinical relevance of deletion and microdeletion syndromes depend on the region of DNA that is deleted and the genes involved