1. A chromosome formed by duplication of one arm and loss of the other arm, resulting in two identical copies of genetic material from one side of the centromere.
Usage: genetics; cytogenetics; technical term

Examples

• An isochromosome can arise when a chromosome breaks at the centromere and one arm is duplicated while the other is lost.
• The patient's karyotype revealed an isochromosome 12p, indicating duplication of the short arm of chromosome 12.
• Isochromosomes are often associated with genetic disorders due to the imbalance of genetic material they create.
• In cytogenetic analysis, an isochromosome appears as a symmetrical structure under the microscope.
• The formation of an isochromosome typically results from abnormal chromosome segregation during cell division.