Genomic imbalance refers to an abnormality in the number or structure of chromosomes within a cell. This can occur when there is a gain or loss of genetic material, leading to an uneven distribution of genes. Such imbalances can result in various health issues, including developmental disorders and certain types of cancer. Common examples of genomic imbalance include trisomy, where an extra chromosome is present, and deletion syndromes, where a portion of a chromosome is missing. These imbalances can disrupt normal cellular functions and contribute to disease progression, making their study important in genetics and medicine.