What DNA sequences does Giemsa stain?

Chromosomes are visualized using Giemsa staining (G-banding). Light bands represent early replicating regions, rich in guanine and cytosine nucleotides. Dark bands represent late replicating regions, rich in adenine and thymine nucleotides.

What causes dark bands on chromosomes?

A karyotype analysis usually involves blocking cells in mitosis and staining the condensed chromosomes with Giemsa dye. The dye stains regions of chromosomes that are rich in the base pairs Adenine (A) and Thymine (T) producing a dark band.

Why is Giemsa staining used in karyotyping?

G-banding, G banding or Giemsa banding is a technique used in cytogenetics to produce a visible karyotype by staining condensed chromosomes. It is useful for identifying genetic diseases through the photographic representation of the entire chromosome complement.

Which stain is used to find chromosomes?

Giemsa
Giemsa is a visible light dye that binds to DNA through intercalation and thus, is used for chromosome staining.

Is Giemsa stain acidic or basic?

Principle of Giemsa Stain Azure and eosin are acidic dye that variably stains the basic components of the cells like the cytoplasm, granules etc. Methylene blue acts as the basic dye, which stains the acidic components, especially the nucleus of the cell.

What causes a dark band on the chromosome and what is this called?

One of the basic chromosomal banding patterns is that produced by Giemsa reagent, a DNA stain applied after mild proteolytic digestion of the chromosomes. This reagent produces patterns of light-staining (G-light) regions and dark-staining (G-dark) regions.

Why trypsin is used in G banding?

Trypsin partially digests some of the chromosomal proteins, thereby relaxing the chromatin structure and allowing the Giemsa dye access to the DNA. In general, heterochromatic regions, which tend to be AT-rich DNA and relatively gene-poor, stain more darkly in G-banding.

What is principle of Giemsa stain?

PRINCIPLE: The “neutral” dyes combining the basic dye methylene blue and the acid dye eosin, give a wide color range when staining. The pH of the staining solution is critical and ideally should be adjusted for different fixatives.

What is true of Giemsa staining?

Giemsa stain is a gold standard staining technique that is used for both thin and thick smears to examine blood for malaria parasites, a routine check-up for other blood parasites and to morphologically differentiate the nuclear and cytoplasm of Erythrocytes, leucocytes and Platelets and parasites.

What kind of blood stain is Giemsa stain?

Giemsa stain is a classic blood film stain for peripheral blood smears and bone marrow specimens.

How is the Giemsa stain used in Drosophila?

It can be used for histopathological diagnosis of malaria and some other spirochete and protozoan blood parasites. It is also used in Wolbachia cell stain in Drosophila melanogaster . Giemsa stain is a classic blood film stain for peripheral blood smears and bone marrow specimens.

How to remove Wright’s stain from Giemsa stain?

If staining with Giemsa (as a thick film) will be delayed for more than 3 days or if the film will be stained with Wright’s stain, lyse the RBCs on the thick film by placing the slide in buffered water (pH 7.0 to 7.2) for 10 min, remove it from the water, and place it in a vertical position to air dry.

How long should a 10% Giemsa smear be used?

One alternate is 10 minutes in 10% Giemsa; the shorter stains yield faster results, but use more stain and might be of less predictable quality. To ensure that proper staining results have been achieved, a positive smear (malaria) should be included with each new batch of working Giemsa stain.