GENE DUPLICATIONS IN EVOLUTIONARY INNOVATION

"𝔾𝕖𝕟𝕖 𝕕𝕦𝕡𝕝𝕚𝕔𝕒𝕥𝕚𝕠𝕟 𝕡𝕣𝕠𝕧𝕚𝕕𝕖𝕤 𝕒 𝕣𝕖𝕕𝕦𝕟𝕕𝕒𝕟𝕔𝕪 𝕥𝕙𝕒𝕥 𝕗𝕣𝕖𝕖𝕤 𝕠𝕟𝕖 𝕔𝕠𝕡𝕪 𝕗𝕣𝕠𝕞 𝕤𝕖𝕝𝕖𝕔𝕥𝕚𝕧𝕖 𝕔𝕠𝕟𝕤𝕥𝕣𝕒𝕚𝕟𝕥, 𝕒𝕝𝕝𝕠𝕨𝕚𝕟𝕘 𝕚𝕥 𝕥𝕠 𝕖𝕩𝕡𝕝𝕠𝕣𝕖 𝕟𝕖𝕨 𝕗𝕦𝕟𝕔𝕥𝕚𝕠𝕟𝕒𝕝 𝕤𝕡𝕒𝕔𝕖." - Dr. Richard Lewontin

🧬 Gene duplications are a driving force in evolution, offering raw material for innovation. They arise through mechanisms like unequal crossing over, retroposition, or whole-genome duplication (WGD). Once a gene is duplicated, one copy can conserve its original role, while the other diverges; fueling new functions, adaptations, or even nonfunctionalization (pseudogenes).

          🔹 The evolutionary fates of gene duplications includes:

Subfunctionalization: split ancestral functions across duplicates.

Neofunctionalization: gain of new roles, which is vital for innovation.

Pseudogenization: loss of function.

A classic case is the globin gene family: duplications enabled the evolution of hemoglobin variants adapted to diverse oxygen environments; from deep-sea species to high-altitude dwellers.

          🔹 Lactase persistence, allowing adults to digest dairy, arose from gene duplications and subsequent regulatory changes; illustrating how duplications shape cultural and demographic shifts.

          🔹 WGDs in flowering plants and vertebrates provided genetic complexity that spurred phenotypic diversity and new lineages.

          ➡️ Gene duplications are not always beneficial. Redundancy can disrupt regulatory balance, contributing to diseases such as cancer, developmental disorders, and infertility complications when expression goes awry.

⚠️ In an Oystershell, gene duplications are both an opportunity and a risk, but their overall impact on biodiversity and innovation is undeniable. They remain a linchpin of evolutionary theory and a key to understanding genomic complexity.

Abubakar Abubakar ✍🏻

• Ohno, S. (1970). Evolution by Gene Duplication.