banding

The process of differential staining of (usually) metaphase chromosomes of cells to reveal the characteristic patterns of bands that permit identification of individual chromosomes and recognition of missing segments; each of the 22 pairs of human chromosomes and the X and Y chromosomes has an identifying b. pattern.

- BrDu-b. labeling of chromosomes in proliferating tissue by adding an excess of bromodeoxyuridine, which replaces the uridine incorporated in RNA and fluoresces in ultraviolet light; the bands result from sister chromatid exchanges.

- high-resolution b. b., especially in prophase, which increases the clarity and number of discernible chromosome bands.

- NOR-b. a procedure which utilizes a silver stain that preferentially accumulates in the nucleoli-organizing regions, i.e., the satellite regions of the acrocentric chromosomes.

- prometaphase b. b. done in the stage of mitosis intermediate between prophase and metaphase.

- pulmonary artery b. a surgical method of decreasing pulmonary blood flow and thereby volume overload of the left ventricle, alleviating CHF in certain congenital heart defects.

- reverse b. See R-b. stain.

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band·ing (bandґing) 1. the act of encircling and binding with a thin strip of material. 2. chromosome b.