In part four of her six-part series on family history and wellbeing, Emma Jolly explores the field of epigenetics and asks whether, as genealogists, we should give credence to the theory that trauma can impact down the generations
What is epigenetics?
Epigenetics – or the study of changes in gene expression not caused by alterations in DNA sequences – is becoming of increasing interest to today’s family historians. Moving away from traditional genealogy, epigenetics may add a new dimension by exploring the potential transgenerational transfer of trauma and the impact of historical events on our genes. This revelation opens up research possibilities, as families seek to comprehend their heritage better and understand the complexities that shape their identities. It also offers an area for family historians to work more closely with psychologists. However, the subject is not without controversy and there are arguments over whether it is scientifically accurate for the term epigenetics to be used at all in the area of human psychology.
Although the word ‘epigenesis’ has been in English usage since the 17th century, it was only in the early 1940s that Conrad Waddington (1905-75), an embryologist and later professor of animal genetics at the University of Edinburgh, introduced the term epigenetics. He defined epigenetics as ‘the branch of biology which studies the causal interactions between genes and their products, which bring the phenotype into being’. The Oxford Dictionary of Biochemistry and Molecular Biology currently defines epigenetics as ‘The study of factors that influence gene expression but do not alter genotype, such as chromatin methylation and acetylation involved in tissue-specific patterns of gene expression, or the parental imprinting of genes.’
Nevertheless, there remains no absolute consensus on how the term is used. It can thus be difficult to have a conversation around epigenetics as not everyone understands it in the same way. In 2015, entomologist Carrie Deans and biologist Keith A. Maggert highlighted how ‘different investigators ascribe different definitions’. While ‘some employ epigenetics to explain changes in gene expression’, for others it is used for ‘transgenerational effects and/or inherited expression states’. This disagreement on a clear definition, they argue, ‘has
