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updated: April 16, 2024


An inversion in a chromosome occurs when a segment breaks off and reattaches within the same chromosome, but in reverse orientation. DNA may or may not be lost in the process.



Inversion. An inversion occurs when part of your chromosome breaks off and then reattaches, but sometimes pieces along the edges are lost. Think of it as though you are reading the newspaper. Sometimes an internal page can get reversed. All the information is still there, but when you go to read the page, it doesn't make any sense. Therefore, having an inversion is an important complication.

Ellen Sidransky
Ellen Sidransky, M.D.

Chief and Senior Investigator

Medical Genetics Branch