Understanding Epistasis

What is epistasis primarily concerned with?

• Environmental effects on genes

• Chromosomal abnormalities

• Gene interactions

• Single gene mutations

In the example of mice coat color, what is the observed phenotypic ratio?

• 9:3:3:1

• 9:3:4

• 9:7

• 3:1

What does a capital B allele signify in the context of mice coat color?

• Brown coat

• No coat color

• White coat

• Gray coat

What happens if a mouse has two lowercase c alleles?

• It will have a gray coat

• It will have no coat

• It will have a brown coat

• It will have a white coat

What is the role of gene C in mice coat color?

• Determines the length of the coat

• Prevents coat color

• Allows pigmentation to develop

• Determines the coat pattern

What should you consider if you observe a 9:3:4 ratio in a dihybrid cross?

• Incomplete dominance

• Epistasis

• Linkage

• Codominance

What is the main takeaway regarding phenotypic ratios in dihybrid crosses?

• They always follow a 9:3:3:1 ratio

• Different ratios can indicate epistasis

• Ratios are irrelevant in genetic studies

• They are always 1:2:1

Which of the following is another common epistasis ratio mentioned?

• 9:3:3:1

• 9:7

• 3:1

• 1:2:1

What is the significance of a 9:7 ratio in genetic studies?

• It indicates codominance

• It suggests epistasis

• It shows incomplete dominance

• It implies genetic linkage

What future topic is briefly mentioned in the video?

• Natural selection

• Complementation

• Genetic drift

• Gene therapy