Question

charcot-marie-tooth disease is a disease of the peripheral nerves caused by a duplication of a gene on chromosome 17 in humans. where could the duplicated gene have originated? select all that apply. the sister chromatid a non-sister chromatid within the homologous pair a replication error during mitosis an unrelated chromosome

Explanation:

• Gene duplications can arise from unequal crossing over between sister chromatids, which copies a segment from one sister chromatid to the other.
• Unequal crossing over between non-sister chromatids of a homologous pair can also lead to one chromatid gaining a duplicated gene segment.
• Replication errors during mitosis (or DNA replication in general) can cause accidental duplication of a gene sequence as DNA is copied.
• A duplicated gene on chromosome 17 would not originate from an unrelated chromosome, as that would be a translocation, not a duplication of the existing gene on this chromosome.

Answer:

• The sister chromatid
• A non-sister chromatid within the homologous pair
• A replication error during mitosis