How PCR, qPCR and STR typing work — the scientific basis behind racing pigeon gene testing.
Polymerase Chain Reaction
The core technique for amplifying a specific DNA fragment in vitro. Through three temperature stages — denaturation, annealing and extension — a trace amount of target DNA is amplified exponentially, up to millions of copies, so that even extremely small amounts of genetic material can be detected.
Application: The foundational technique for gene locus testing and pathogen nucleic acid detection.
Real-time Quantitative PCR
A fluorescent probe is added to the PCR reaction to monitor amplification in real time. The shape of the fluorescence curve (Ct value) quantifies the initial amount of target nucleic acid, with high sensitivity and specificity, so that even very low copy numbers of pathogen nucleic acid can be detected.
Application: Used for pathogen detection and quantification, enabling early detection before clinical signs appear.
Short Tandem Repeat
STRs are short sequences of 2–6 bases that repeat in the genome, and the number of repeats varies widely between individuals. By genotyping the repeat-number combination at multiple STR loci, a DNA fingerprint unique to each racing pigeon can be built.
Application: Used to establish a DNA ID and for parentage testing.
Single Nucleotide Polymorphism
A SNP is a variation at a single base in the genome, and an important genetic basis for differences in biological traits. Genotyping candidate-gene SNP loci associated with racing pigeon traits assesses the genetic tendency of traits related to racing performance — a statistical association drawn from published pigeon research, not a causal claim.
Application: Used for genotype analysis at candidate-gene loci associated with flight performance — a genetic reference for breeding decisions, always read alongside performance records.
High-quality genomic DNA is extracted from feather pulp, blood cards or swab samples.
PCR/qPCR specifically amplifies the target gene loci or pathogen nucleic acid.
Fluorescence signals or electrophoresis bands are read to obtain the genotype or pathogen detection result.
Genotypes are called and results interpreted against reference databases and quality-control standards.
⚠️ Scope of service: all tests are for racing pigeons and other birds (avian/veterinary use) only. They are not intended for human medical diagnosis.
Why use PCR rather than sequencing?
For genotyping known loci, PCR is faster, costs less and can test many samples in a single batch; whole-genome sequencing gives more complete information but costs more and is better suited to research settings.
What is the difference between SNP and STR?
A SNP is a single-base variation, used for trait association analysis; an STR is a difference in repeat number, with high polymorphism, suited to individual identification and parentage testing. The two uses are complementary.
Does the environment affect testing?
DNA sequence does not change with the environment, but sample contamination or poor storage will affect the reliability of results — which is why standardised sampling and quality control procedures matter.
