1. What is DNA Copy Number Calculation?

The DNA copy number calculation determines the number of molecules present in a given mass of DNA. It's essential for molecular biology applications like PCR, sequencing, and cloning where knowing the exact number of DNA molecules is crucial.

2. How Does the Calculator Work?

The calculator uses the copy number formula:

Where:

• \( CN \) — Copy number (dimensionless)
• \( C \) — DNA concentration (grams)
• \( MW \) — Molecular weight (grams per mole)
• \( 6.022 \times 10^{23} \) — Avogadro's number (molecules per mole)

Explanation: The formula converts mass of DNA to number of molecules using Avogadro's number and the molecular weight of the DNA.

3. Importance of Copy Number Calculation

Details: Accurate copy number calculation is vital for quantitative experiments, ensuring proper template amounts in PCR, and normalizing samples in next-generation sequencing.

4. Using the Calculator

Tips: Enter DNA concentration in grams and molecular weight in g/mol. Both values must be positive numbers. For typical dsDNA, MW can be calculated as (length in bp) × 650 g/mol/bp.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine molecular weight of my DNA?
A: For double-stranded DNA, multiply the length in base pairs by ~650 g/mol/bp. For single-stranded DNA, use ~330 g/mol/nt.

Q2: What units should I use for concentration?
A: The calculator expects grams, but you can convert from ng/μL by multiplying concentration by volume and appropriate unit conversions.

Q3: Why is Avogadro's number used?
A: Avogadro's number (6.022×10²³) converts between moles (molecular weight) and individual molecules.

Q4: Can this be used for RNA?
A: Yes, the same formula applies for RNA molecules when using the correct molecular weight.

Q5: What's a typical copy number range for PCR?
A: Most PCRs use 10³-10⁶ copies as template, depending on application and detection sensitivity.