Gene duplication

Definition

Gene duplication is a process where a segment of DNA that contains a gene is copied, resulting in two identical or nearly identical copies of that gene within the genome. This phenomenon can play a crucial role in molecular evolution, as it allows for genetic redundancy and the potential for one copy to undergo mutations and acquire new functions over time, contributing to biological diversity and the complexity of organisms.

5 Must Know Facts For Your Next Test

1. Gene duplication can occur through various mechanisms, including unequal crossing over during meiosis, replication errors, or transposable elements.
2. Duplicated genes may either retain their original function, become non-functional (pseudogenes), or evolve new functions through mutations.
3. Gene duplication is believed to be a significant driver of evolutionary innovation, providing raw material for the development of new traits and adaptations.
4. The presence of gene duplicates can lead to increased genetic robustness, as one copy can compensate for the loss or malfunction of another.
5. Studies have shown that gene duplication events are often associated with key evolutionary transitions and the emergence of complex traits in various organisms.

Review Questions

• How does gene duplication contribute to molecular evolution and what are some potential outcomes of this process?
  • Gene duplication contributes to molecular evolution by providing additional genetic material that can undergo mutations. This redundancy allows one copy of the gene to maintain its original function while the other can evolve new functions or become non-functional. Over time, this process can lead to functional divergence, where duplicated genes develop different roles, ultimately enhancing biological diversity and enabling organisms to adapt to changing environments.
• Discuss the relationship between gene duplication and homologous genes. How does this connection enhance our understanding of evolutionary biology?
  • Gene duplication is directly related to homologous genes since duplicated genes typically share a common ancestry. This connection allows researchers to trace evolutionary relationships between species by examining the similarities and differences in gene sequences. By studying homologous genes across various organisms, scientists can infer how gene duplication has contributed to the diversification of life and the emergence of complex traits throughout evolutionary history.
• Evaluate the significance of functional divergence following gene duplication in shaping organismal complexity and adaptability. What implications does this have for understanding evolutionary mechanisms?
  • Functional divergence following gene duplication is significant because it allows organisms to develop specialized functions from initially redundant genetic material. This process not only fosters organismal complexity but also enhances adaptability by enabling different strategies for survival and reproduction. Understanding how gene duplication leads to functional divergence provides insights into evolutionary mechanisms, highlighting how genetic variation drives innovation and adaptation in response to environmental pressures.

Related terms

Mutation: A change in the DNA sequence that can lead to variations in genes, potentially resulting in new traits or functions.

Homologous Genes: Genes that share a common ancestry and typically retain similar sequences and functions across different species due to evolutionary relationships.

Functional Divergence: The process by which duplicated genes evolve different functions over time, leading to diversification in the roles they play within an organism.