American Society for Clinical Pathology (ASCP) Technologist in Cytogenetics certification (ASCP CG) Practice Test

What type of stained chromosome is recommended for producing a better computer image?

1. Heavily stained chromosomes

2. Lightly stained chromosomes

3. Unstained chromosomes

4. Fluorescently stained chromosomes

The correct answer is: Lightly stained chromosomes

Lightly stained chromosomes are recommended for producing a better computer image because they provide the optimal contrast needed for computer analysis and imaging. When chromosomes are lightly stained, the bands and structures are distinct enough to be visualized clearly without overwhelming background staining. This allows for better differentiation of chromosomal features, which is crucial for accurate identification in cytogenetic studies. In contrast, heavily stained chromosomes may obscure fine details due to excessive coloration, making it challenging to discern the structures necessary for analysis. Unstained chromosomes do not provide any contrast, rendering them nearly invisible under standard imaging techniques, which is not suitable for effective evaluation. Fluorescently stained chromosomes can also be useful in some contexts, particularly for specific analyses like FISH (Fluorescence In Situ Hybridization), but they can introduce complexity with color interpretation and may not be as universally applicable for all types of computer imaging as lightly stained chromosomes.