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Genetic disorders traditionally fall into 3 main categories: single-gene defects, chromosomal abnormalities, and multifactorial conditions. A chromosomal abnormality, also known as a chromosomal aberration, is a disorder characterised by a morphological or numerical alteration in one or more chromosomes, affecting autosomes, sex chromosomes, or both. The normal human karyotype contains approximately 2 meters of DNA organized into 46 chromosomes: 22 pairs of homologous autosomal chromosomes and 1 pair of sex chromosomes that comprise 2 X chromosomes in females or 1 X and 1 Y chromosome in males. All the genetic material necessary for growth and development is derived from these chromosomes (about 20,000 to 25,000 genes). Chromosome abnormalities typically result from errors in cell division (mitosis or meiosis) that may occur during the prenatal, postnatal, or preimplantation periods. These alterations have significant clinical consequences, including spontaneous abortions, stillbirths, neonatal death or hospitalization, malformations, intellectual disability, or identifiable syndromes. Accurate identification of these chromosomal errors is essential for prevention strategies, genetic counseling, and appropriate treatment.