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PCR

Definition

Polymerase Chain Reaction. Kary Mullis 1983. Exponential amplification of a target sequence using a thermostable Taq polymerase, two primers and thermal cycling.

Related terms

Autosomal vs Mitochondrial DNA
Autosomal DNA is nuclear, biparentally inherited, present as two copies per cell. Mitochondrial DNA is cytoplasmic, maternally inherited, present in hundreds to...
Capillary Electrophoresis
Size separation of fluorescently labelled PCR products through a polymer-filled capillary on an instrument like the ABI 3500. Output is an electropherogram.
Chromosome
A discrete, condensed structure consisting of a single long DNA molecule complexed with histone proteins. Humans normally carry 46 chromosomes in 23...
CODIS
The FBI's Combined DNA Index System, the US national STR-based forensic DNA database. Contains profiles from convicted offenders, arrestees, and unidentified crime-scene...
Multiplex STR Kit
Single-tube PCR amplifying 15+ STR loci plus amelogenin in one reaction. AmpFISTR Identifiler Plus and PowerPlex are the workhorses in Indian DNA...
Nucleotide
The monomer unit of nucleic acids. Each nucleotide consists of a five-carbon sugar (deoxyribose in DNA, ribose in RNA), a phosphate group,...
RFLP
Restriction Fragment Length Polymorphism. The first-generation DNA typing method using restriction enzymes and Southern blotting. Required nanograms of intact DNA.
SNP (Single Nucleotide Polymorphism)
A position in the genome where the nucleotide base differs between individuals. Genome-wide SNP panels are more powerful than STR panels for...
STR (Short Tandem Repeat)
A genomic locus where a 2, 7 base-pair unit is repeated in tandem a variable number of times between individuals. The variation...
VNTR
Variable Number Tandem Repeats. Longer repeat units (10 to 100 bp) than STRs. The original Alec Jeffreys 1984 fingerprinting markers, now superseded...
Watson-Crick Base Pairing
Adenine pairs with thymine via two hydrogen bonds; guanine pairs with cytosine via three. The pairing rule that makes the double helix...

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