Practical applications of PCR PCR is a versatile method used in which of the following areas of modern biology and medicine?
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ATo diagnose genetic diseases
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BTo solve crimes
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CTo study gene function
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DAll of these
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EOnly in basic research, not in clinical or forensic work
Answer
Correct Answer: All of these
Explanation
Introduction / Context:PCR underpins modern diagnostics, forensics, and research. Its sensitivity and specificity make it ideal for detecting tiny amounts of nucleic acid in diverse contexts.
Given Data / Assumptions:
- Amplification of defined DNA targets is possible from minute samples.
- Appropriate controls and standards are used for accuracy.
- Downstream methods (sequencing, qPCR) can refine results.
Concept / Approach:In diagnostics, PCR detects mutations, pathogens, and gene fusions. In forensics, STR loci are amplified for human identification. In research, PCR enables cloning, site-directed mutagenesis, and gene expression (via RT-PCR).
Step-by-Step Solution:Define the target and design primers/probes.Optimize cycling conditions and Mg2+ concentration.Analyze amplicons by gel, melt curves, or sequencing.
Verification / Alternative check:Inclusion of positive/negative controls and standard curves (qPCR) ensures specificity and quantitation.
Why Other Options Are Wrong:Limiting PCR to one domain ignores its established use across diagnostics, forensics, and research.
Common Pitfalls:Contamination leading to false positives; primer-dimers; mispriming.
Final Answer:All of these.