Glossary
Genotype
The combination of alleles an individual carries at a particular gene locus.
Phenotype
The observable characteristics an individual shows, determined by genotype and environment together.
Allele
A different version of a gene at the same gene locus.
Homozygote
An individual whose two alleles at a gene locus are identical (such as AA, aa).
Heterozygote
An individual whose two alleles at a gene locus differ (such as Aa).
Dominant
An allele whose trait is expressed even in the heterozygous state.
Recessive
An allele whose trait is expressed only in the homozygous state.
Punnett Square
A genetics diagram used to predict the genotype and phenotype probabilities of the offspring.
Mendelian Inheritance
The inheritance rules revealed by Mendel, including the law of segregation and the law of independent assortment.
Law of Independent Assortment
Alleles at different gene loci are distributed independently when gametes form.
STR Marker Short Tandem Repeat
A short tandem repeat sequence whose repeat number varies greatly between individuals, used for parentage testing.
Parentage Consistency
The degree to which every allele of the offspring can be traced to a source in the genotypes of its parents.
DNA Identity
An individual-specific genetic fingerprint profile built from STR markers.
SNP Single Nucleotide Polymorphism
A single-base variation in the genome; a core marker for genetic testing.
Quantitative Trait
A trait influenced by many genes and by the environment together, showing a continuous distribution (such as racing performance).
Heritability
The proportion of phenotypic variation explained by genetic factors; it affects the expected response to selection.
Inbreeding Coefficient (F)
The probability that an individual carries two alleles that are identical by descent, measuring the degree of inbreeding.
Association
A statistical association between a genotype and a trait, which is not the same as causation; association ≠ causation is the first principle when interpreting a test report.