Pigeons have long been the subject of genetic studies. Indeed, Charles Darwin bred pigeons in the hope of unraveling the principles of heredity but was unsuccessful. A series of genetic investigations in the early 1900s worked out the hereditary basis of color variation in these birds. W. R. Horlancher was interested in the genetic basis of kiteness, a color pattern that consists of a mixture of red and black stippling of the feathers. He carried out the following crosses to investigate the genetic relation of kiteness to black and red feather color (W. R. Horlancher. 1930. Genetics 15:312–346). Cross Offspring kitey × kitey 16 kitey, 5 black, 3 red kitey × black 6 kitey, 7 black red × kitey 18 red, 9 kitey, 6 black a. On the basis of these results, propose a hypothesis to explain the inheritance of kitey, black, and red feather color in pigeons. (Hint: Assume that two loci are involved and some type of epistasis occurs.) b. For each of the preceding crosses, test your hypothesis by using a chisquare test.
Genetic Variation
Genetic variation refers to the variation in the genome sequences between individual organisms of a species. Individual differences or population differences can both be referred to as genetic variations. It is primarily caused by mutation, but other factors such as genetic drift and sexual reproduction also play a major role.
Quantitative Genetics
Quantitative genetics is the part of genetics that deals with the continuous trait, where the expression of various genes influences the phenotypes. Thus genes are expressed together to produce a trait with continuous variability. This is unlike the classical traits or qualitative traits, where each trait is controlled by the expression of a single or very few genes to produce a discontinuous variation.
Pigeons have long been the subject of genetic studies. Indeed,
Charles Darwin bred pigeons in the hope of unraveling the principles of
heredity but was unsuccessful. A series of genetic investigations in the
early 1900s worked out the hereditary basis of color variation in these
birds. W. R. Horlancher was interested in the genetic basis of kiteness, a
color pattern that consists of a mixture of red and black stippling of the
feathers. He carried out the following crosses to investigate the genetic
relation of kiteness to black and red feather color (W. R. Horlancher.
1930. Genetics 15:312–346).
Cross Offspring
kitey × kitey 16 kitey, 5 black, 3 red
kitey × black 6 kitey, 7 black
red × kitey 18 red, 9 kitey, 6 black
a. On the basis of these results, propose a hypothesis to explain the
inheritance of kitey, black, and red feather color in pigeons. (Hint: Assume
that two loci are involved and some type of epistasis occurs.)
b. For each of the preceding crosses, test your hypothesis by using a chisquare
test.
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 6 images
