What is Giemsa stains?

Giemsa staining is a very important method for various pathological test,histological studies.

Giemsa stains are used  to stain peripheral blood and bone marrow . The important components of these stains are oxidized methylene blue, azure B and eosin Y dyes. The eosin Y dye stains the cytoplasm of cells an orange to pink color. The methylene blue and azure B dyes stain the nucleus varying shades of blue to purple. 

Giesma stains are used to perform differential white blood cell counts and to study red blood cell morphology. Abnormal granulocyte, lymphocyte or monocyte cell counts may be used to facilitate the diagnosis of diseases such as leukemia or bacterial infections.

It stains DNA. As such, it can be used to stain any DNA-containing organism, or, in other words, any known cell.This stains is also used to label chromosome and that is called as chromosomal banding.This is called due to fact that the G-bands are most commonly used,which is due to  Giemsa dye, but can be produced with other dyes. In G-bands, the dark regions tend to be heterochromatic, late-replicating and AT rich. The bright regions tend to be euchromatic, early-replicating and GC rich.

This technique is very useful to study cellular division process as we it can specifically target and stain various region inside the chromosome

Staining reveals structural features of the chromosomes in metaphase by banding. Giemsa staining offers better resolution of individual bands of chromosomes along the length of the whole chromosome. It stains DNA to heterochromatic (dark) and euchromatic (white) regions resulting into G-bands, called so because of the dye Giemsa, used in staining historically first, but can be stained also with other dyes. It stains any DNA-containing organism, or, in other words, any known cell. Analysis involves the karyotyping of banded metaphase chromosomes.