. Chromosomal Abnormalities Each human diploid (2n) body cell has chromosomes ( pairs). Chromosomal disorders are caused by errors in the number or structure of chromosomes. Chromosomal anomalies usually occur when there is an error in cell division.
Failure of chromatids to segregate during cell division resulting in the gain or loss of one or more chromosomes is called aneuploidy. It is caused by non- disjunction of chromosomes. Group of signs and symptoms that occur together and characterize a particular abnormality is called a syndrome. In humans, Down’s syndrome, Turner’s syndrome, Klinefelter's syndrome, Patau’s syndrome are some of the examples of chromosomal disorders.