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Updated: Jun 8, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
The gene revisited: historical foundations and postgenomic complexity
Megha Rani Maji1, Prashant Shukla2
1Department of Biotechnology, Brainware University, Barasat, West Bengal, 700125, India.
Summary
The definition of a gene has evolved significantly over a century, moving from simple Mendelian heredity to complex genomic interactions. A new working definition integrates DNA sequence and transcriptional output for modern biological practice.
Area of Science:
- Genetics and Genomics
- Molecular Biology
- Conceptual Biology
Background:
- The gene concept, central to biology for over 100 years, faces challenges reconciling historical definitions with modern molecular and genomic data.
- Early gene models assumed discrete units with stable trait relationships, which proved insufficient with discoveries in gene regulation and epigenetics.
Purpose of the Study:
- To examine the historical evolution of the gene concept from classical genetics to postgenomic biology.
- To analyze the conceptual and empirical challenges in defining the gene amidst new biological discoveries.
- To propose a pragmatic, contemporary working definition of the gene.
Main Methods:
- Historical review of genetic and molecular biology literature.
- Conceptual analysis of evolving gene definitions.
- Synthesis of key developments across classical genetics, molecular biology, and genomics.
Main Results:
- The gene concept has expanded significantly, accommodating complex phenomena like gene regulation, RNA processing, and epigenetic modifications.
- Empirical definition of the gene is challenging due to its multifaceted nature and the vastness of genomic information.
- Despite definitional challenges, the gene remains an indispensable concept in biological research and practice.
Conclusions:
- A pragmatic working definition of the gene is proposed, emphasizing DNA sequence and reproducible, regulated transcriptional output.
- This definition aims to bridge the gap between historical gene concepts and contemporary genomic research.
- The gene, though complex, continues to be a fundamental and essential organizing principle in biology.
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