Cytogenetic testing is a basic genetic test in which the patient’s chromosomal makeup is examined from a sample of the patient’s blood.
Blood cells contain DNA in their nucleus, which carries genetic information. At a certain stage of cell division, the DNA is visible in the form of fibrous, easily stained formations; the assembly of these formations produces the human karyotype and the examination is called karyotyping. There are international rules governing the examination and description of the human karyotype that are followed in all accredited cytogenetic laboratories.
The normal human karyotype has 22 pairs of chromosomes, (one pair is from the mother, the other from the father) and 2 sex chromosomes that determine the sex of the individual.
