Karyotyping is a process used by scientists to examine chromosomes for abnormalities in structure and number. Types of mutations include deletion, duplication, inversion, and translocation. Nondisjunction can also occur during meiosis, which is a failure of homologous chromosomes or sister chromatids to separate. This causes individuals to have the incorrect number of each chromosome. The most common occurrence is trisomy (three copies of a chromosome) and monosomy (only one copy of a chromosome).
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