testcross

test·cross

noun \ˈtes(t)-ˌkrȯs\

Definition of TESTCROSS

: a genetic cross between a homozygous recessive individual and a corresponding suspected heterozygote to determine the genotype of the latter

— testcross transitive verb

First Known Use of TESTCROSS

1934

test·cross

noun \ˈtes(t)-ˌkrȯs\   (Medical Dictionary)

Medical Definition of TESTCROSS

: a genetic cross between a homozygous recessive individual and a corresponding suspected heterozygote to determine the genotype of the latter

—testcross transitive verb

testcross

noun    (Concise Encyclopedia)

Experiment in which an organism with unknown genetic makeup is mated with an organism whose entire genetic makeup for a trait is known, to determine which genes are carried by the former. In a breed of dog, for example, in which the gene for black coat colour is dominant over the gene for red coat colour (see dominance), a dog with a black coat may be pure (with two genes for black coat colour) or hybrid (with one gene for black and one for red). When its mating with a red-coated dog (which always has two genes for red coat colour only) produces only black offspring, the black-coated parent must be pure, whereas if some of the young are red, the parent must be hybrid.