Allred 39 Flashcards
Phenotype
The observable property of an organism; a trait such as height, weight, medical condition, etc.
Genotype
The DNA sequence of an organism in a specific, defined location
Allele
A DNA sequence at a specific location on the chromosome
All DNA sequences are alleles
Homozygous
Two identical alleles carried at the same locus
Heterozygous
Two nonidentical alleles carried at the same locus
Dominant Trait
At a heterozygous allele, the copy of the gene that is phenotypically expressed
Recessive Trait
An allele that can only be expressed when both copies are present; not expressed in a heterozygous allele with a dominant allele
Codominant Trait
At a heterozygous allele; both copies of the gene are phenotypically expressed
Locus
A specific location on a chromosome
Recombination
Allows geneticists to observe and measure recombination. In combination with the concepts of phenotype and genotype enables geneticists to locate the genes on the chromosomes of complex organisms
Recombination fraction
Recombinants / Total Progeny
Expressed as [theta]
Linkage
Two loci inherited together as a result of their position on the same chromosome; measured by percentage of recombination
Benefits of genetic methods
Helps determine if traits are on the same or different chromosome
Helps determine distance if the gene is on the same chromosome; allows for the creation of genetic maps
Recobinant inbred mice (benefits)
Systematic inbreeding following a cross between two inbred strains (sib-pairs)
Allows mapping of a new gene by comparing its pattern of inheritance to patterns for other previously mapped genes in the same set of recombinant inbred strains
Congenic mice
Back-crossing mice
Isolates a gene of interest in a background that is genetically different; gives a way to localize the genes or genes
