Do chromosomal duplications trigger epigenetic effects in autism?

PostedNovember 19, 2025

UpdatedNovember 19, 2025

ByMy Patient Advice

Author: Lucia Alvarez, MSc | Reviewed by: Dr. Rebecca Fernandez, MBBS

Yes, certain chromosomal duplications have been found to trigger epigenetic changes that may contribute to autism. A chromosomal duplication occurs when a segment of DNA is copied more than once, leading to extra genetic material in the genome. This can disrupt normal gene balance and, in turn, influence how genes are expressed through epigenetic mechanisms such as DNA methylation or histone modification.

In autism, duplications on chromosomes like 15q11–q13 or 16p11.2 are among the most studied. These regions contain genes linked to brain development and function, and when duplicated, they can upset the finely tuned control of gene activity. These disruptions often extend beyond the duplicated segment itself, affecting wider genetic networks through altered epigenetic regulation. This interaction between genetics and epigenetics is key to understanding the layered complexity of autism’s biological origins.

How Chromosomal Duplications Influence Epigenetics

Here are two ways chromosomal duplication can lead to epigenetic effects:

Disrupts gene dosage and expression

When genes are duplicated, they can become overactive. This change in dosage may lead to compensatory epigenetic responses, such as increased DNA methylation, to restore balance. In some cases, these changes contribute to altered brain development and autistic traits.

Triggers widespread chromosomal effects

Duplications can influence not only nearby genes but also distant regions, affecting how the genome is folded and read. These chromosomal effects may interfere with how other unrelated genes are regulated, adding complexity to autism’s presentation.

Recognising the epigenetic consequences of chromosomal duplication helps deepen our understanding of autism’s diverse causes. Visit providers like Autism Detect for personal consultations and further guidance on screening and support.

For a deeper dive into the science, diagnosis and full treatment landscape, read our complete guide to Genetic Influences.

Lucia Alvarez, MSc

Author

Lucia Alvarez is a clinical psychologist with a Master’s in Clinical Psychology and extensive experience providing evidence-based therapy and psychological assessment to children, adolescents, and adults. Skilled in CBT, DBT, and other therapeutic interventions, she has worked in hospital, community, and residential care settings. Her expertise includes grief counseling, anxiety management, and resilience-building, with a strong focus on creating safe, supportive environments to improve mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the author's privacy.

Dr. Rebecca Fernandez, MBBS

Reviewer

Dr. Rebecca Fernandez is a UK-trained physician with an MBBS and experience in general surgery, cardiology, internal medicine, gynecology, intensive care, and emergency medicine. She has managed critically ill patients, stabilised acute trauma cases, and provided comprehensive inpatient and outpatient care. In psychiatry, Dr. Fernandez has worked with psychotic, mood, anxiety, and substance use disorders, applying evidence-based approaches such as CBT, ACT, and mindfulness-based therapies. Her skills span patient assessment, treatment planning, and the integration of digital health solutions to support mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the reviewer's privacy.