Comparison of Methods used for DNA Quantification Method

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Comparison of Methods used for DNA Quantification Method Ease Cost UV Spectrophotometry Yield Gel

Comparison of Methods used for DNA Quantification Method Ease Cost UV Spectrophotometry Yield Gel electrophoresis Slot Blot ++ Yield Gel blot + Pico-green microtitre plate Sensitivity +++++ ++ ++++ ++ Alu Quant +++ Real time PCR assays +++ ++++ +++ Result ++ + ++++ Total DNA Int vs deg DNA Human DNA Int. vs. deg human DNA Total DNA +++++ Human DNA Int. vs. deg. Human DNA

Summary 1 (from last week) • Why study DNA – Law enforcement, evolution, agricultural,

Summary 1 (from last week) • Why study DNA – Law enforcement, evolution, agricultural, and human applications-medical diagnostics • DNA Biology and Genetics – DNA is contained in cells –the basic unit of life – Found in nuclei, mitochondria and chloroplasts – Organized in chromosomes. Located at positions called loci and come in different forms or alleles. – Homozygous if the same, heterozygous if different – Alleles segregate independently and assort randomly when on different chromosomes. Random assortment is desired forensic DNA loci. • DNA Function and Structure – Deoxyribo. Nucleic Acid : blueprints of life Replication, Information storage and mutation RIM – Central Dogma DNA------->RNA------>protein

Summary 2 • DNA Structure and Function continued: – – – Bases are Adenine,

Summary 2 • DNA Structure and Function continued: – – – Bases are Adenine, Guanine, Cytosine and Thymine- Asian Guys Can Teach: AGCT Base pairing is A to T and G to C- DNA is where its AT Sequence of Bases Store information- Like the sequence of numbers in a Phone Number Sides of the ladder are Sugar-Phosphate backbones Nucleotides are the building blocks (d. NTPs) themselves made of phosphate base and sugar= PBS- The only station Sierra and Gabriel can watch – DNA base pairs- DNA velcro (David Letterman • DNA Replication – Semi-conservative- Half republican (old) /half democrat (new) – Template directed with base pairing (AT, GC) – 5 required ingredients of PCR - primer, template, Mg, dntps, DNA polymerase (PTMDD)

Summary 3 • Steps in forensic DNA typing are – Evaluation, Extraction, Quantification, Typing

Summary 3 • Steps in forensic DNA typing are – Evaluation, Extraction, Quantification, Typing and Interpretation – 1) Evaluation- Is it there? Screen- blood? Semen? Saliva, human? – 2) Extraction- Get and clean DNA • Open cells -Get DNA • Organic, Chelex and FTA extractions • Quantify- Determine quality and quantity? – How good and how much did you get? – Yield Gels, Slot Blots, Real time PCR assays

Case #2: Can you extract and type DNA from fingerprint powder that has been

Case #2: Can you extract and type DNA from fingerprint powder that has been used to develop latent prints? If so, design an experiment with + and – controls to support your hypothesis.