Cytogenetics is a
branch of Science that deals with analysis of chromosomes. Karyotyping is a
type of conventional cytogenetic technique used for the numerical and
structural analysis of chromosomes in the metaphase stage of cell cycle. It
involves arrangement of all the 46 chromosomes in descending order of their
size with sex chromosomes at the end. The procedure involves culturing of blood
cells for numerous metaphases, harvesting the nucleated white blood cells,
fixing the chromosomes on the glass slides followed by staining and banding of
the chromosomes for further analysis. However, analysis of the chromosomes
require basic knowledge on the identification of chromosomes as each chromosome
show a characteristic banding pattern that differs from one chromosome to
another.
Karyotyping is used in
the field of medicine to detect chromosomal abnormalities in patients with
genetic disorders. The technique has an advantage of detecting chromosomal
abnormality upto 5 MB. Karyotyping helps in the assessment of risk for genetic
disorders in a family. Children with mental retardation, deformed features,
patients with recurrent abortions and infertility problems can also benefit
from the karyotyping and pedigree analyses. A combination of pedigree and
karyotyping analyses would make Genetic counseling a potential service to
family members of the affected individual.