Questions 2-3: The Igf2 gene encodes insulin-like growth factor 2, a protein tha

Question

Questions 2-3: The Igf2 gene encodes insulin-like growth factor 2, a protein that is important for normal growth. In mice, no expression of the Igf2 gene results in a growth deficiency and a small mouse phenotype. The Igf2 gene is maternally imprinted and autosomal.

2. (2pts) A female mouse is homozygous null for the Igf2 gene and mates with a male mouse that is homozygous wildtype. What is the expected phenotypes of their progeny?

1. All small progeny

2. All wildtype progeny

3. 25% small progeny and 75% wildtype progeny

4. 50% small progeny and 50% wildtype progeny

5. 75% small progeny and 25% wildtype progeny

6. All small males and all wildtype females

7. All wildtype males and all small females

1. All small progeny

Explanation / Answer

Answer:

All wild progeny

Explanation.

Maternal imprinting means that the allele of a particular gene inherited from the mother is transcriptionally silent and the paternally- inherited allele is active. For example, the gene encoding insulin-like growth factor 2 (IGF2/Igf2) is only expressed from the allele inherited from the father

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.