What is a mini-STR analysis and when is it advantageous?

What is a mini-STR analysis and when is it advantageous?

• A. Uses longer amplicons to improve specificity.
• B. Requires intact DNA only.
• C. Amplifies mitochondrial DNA exclusively.
• D. Targeting shorter amplicons; advantageous for degraded or compromised DNA.

Answer: (D)

Mini-STR analysis focuses on amplifying shorter segments at STR loci. When DNA is degraded, it tends to be cut into small pieces, so the longer segments targeted by standard STR assays often don’t survive. By using primers that produce smaller PCR products, mini-STRs reach the same loci but with much shorter amplicons, increasing the chance that the DNA fragments remain intact enough to amplify. This yields usable profiles from samples where the DNA quality is compromised, such as aged or heat-damaged specimens, bones, dried stains, or other trace evidence. It’s a nuclear DNA approach and doesn’t require intact DNA, and it’s not about mitochondrial DNA. In practice, mini-STRs improve success with degraded samples while maintaining the ability to discriminate between individuals.

Mini-STR analysis focuses on amplifying shorter segments at STR loci. When DNA is degraded, it tends to be cut into small pieces, so the longer segments targeted by standard STR assays often don’t survive. By using primers that produce smaller PCR products, mini-STRs reach the same loci but with much shorter amplicons, increasing the chance that the DNA fragments remain intact enough to amplify. This yields usable profiles from samples where the DNA quality is compromised, such as aged or heat-damaged specimens, bones, dried stains, or other trace evidence. It’s a nuclear DNA approach and doesn’t require intact DNA, and it’s not about mitochondrial DNA. In practice, mini-STRs improve success with degraded samples while maintaining the ability to discriminate between individuals.