A Chromosomal mutation is a "mutation involving a long segment of DNA" (Northwestern EDU). These mutations involve different forms like deletion, duplication, inversion, insertion, and translocation. These mutations occur when there is a change in the "arrangement or structure of the chromosomes" (Brighthub). To add on, these mutations usually occur because  there was either a problem during the meiosis process or there was a interaction with a mutagen (radiation, chemical, etc) 

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