AGB 121: Principles of Animal Genetics and Population Genetics (2+1)

DELETION

• Deletion is a chromosomal aberration where a segment or a portion of the chromosome is lost.
• Deletions lead to decrease in gene number.
• Deletion was first discovered by Bridges in 1917.
• Deletions are classified into two types based upon the position where deletion occurs.
• Terminal Deletion
• Intercalary / Interstitial Deletion.
• One example: Cri-du-chat syndrome, which result from loss of part of the short arm of chromosome 5. Individuals with this syndrome suffer severe mental and physical impairment, and have a distinctive cry like that of a cat (which gives the syndrome its name).