Final answer:
DiGeorge syndrome is a genetic disorder caused by the deletion of a small piece of chromosome 22. It occurs during the formation of the egg or sperm, or early in embryonic development. The primary cause is a random genetic mutation, and not inherited.
Step-by-step explanation:
DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a genetic disorder caused by the deletion of a small piece of chromosome 22. Specifically, a section of DNA is missing from the long arm of chromosome 22, which leads to various abnormalities and health issues. This deletion occurs during the formation of the egg or sperm, or early in embryonic development.
The primary cause of DiGeorge syndrome is a random genetic mutation, and it is not inherited from parents. The exact reason for this deletion is unclear, but it is believed to result from errors in the recombination or replication of DNA during the development of reproductive cells. These errors can be influenced by certain environmental factors, such as exposure to radiation or certain medications, but the underlying cause is still being studied.