Transgenerational epigenetic inheritance

Inheritance of traits not involving changes to the DNA sequence

Transgenerational epigenetic inheritance refers to the transmission of information from one generation of an organism to the next that affects the traits of offspring without alteration of the primary structure of DNA, that is, the sequence of nucleotides. This phenomenon is a form of epigenetics, which involves changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself.

Mechanisms

Transgenerational epigenetic inheritance can occur through several mechanisms, including DNA methylation, histone modification, and non-coding RNA molecules. These epigenetic marks can be influenced by environmental factors and can be passed on to subsequent generations.

DNA Methylation

DNA methylation involves the addition of a methyl group to the DNA molecule, typically at cytosine bases. This modification can affect gene expression by altering the accessibility of the DNA to transcriptional machinery.

Histone Modification

Histone modification involves changes to the proteins around which DNA is wound. These modifications can influence gene expression by altering chromatin structure and accessibility.

Non-coding RNA

Non-coding RNA molecules can regulate gene expression at the transcriptional and post-transcriptional levels. They can also play a role in the inheritance of epigenetic information.

Examples

One well-documented example of transgenerational epigenetic inheritance is the Agouti mouse model, where the coat color of mice is influenced by the diet of the mother. Another example is the inheritance of stress responses in plants, where exposure to stress can lead to changes in gene expression that are passed on to offspring.

Research and Implications

Research into transgenerational epigenetic inheritance is ongoing, with implications for understanding evolution, developmental biology, and disease. It challenges the traditional view of inheritance and suggests that acquired traits can be passed on to future generations.

Related pages

• Epigenetics
• Genetic inheritance
• Lamarckism

References

• Jablonka, E., & Lamb, M. J. (2005). Evolution in Four Dimensions: Genetic, Epigenetic, Behavioral, and Symbolic Variation in the History of Life. MIT Press.
• Heard, E., & Martienssen, R. A. (2014). Transgenerational epigenetic inheritance: myths and mechanisms. Cell, 157(1), 95-109.

File:Epigenetic Inheritance Through The Female Line.png

Epigenetic inheritance through the female line.

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Blending inheritance, a concept historically contrasted with Mendelian inheritance.