Study Links Genes to Seeing Sounds in Synesthesia

Author: Cell Press
Published: 2009/02/05 - Updated: 2025/05/23
Publication Details: Peer-Reviewed, Informative
Category Topic: Deafness and Hearing Loss - Academic Publications

Page Content: Synopsis - Introduction - Main - Insights, Updates

Synopsis: This peer-reviewed research article, originally published in the American Journal of Human Genetics, investigates the genetic basis of auditory-visual synesthesia - a condition where individuals perceive colors in response to sounds. Conducted by a team from institutions including Imperial College London, the University of Oxford, and the University of Cambridge, the study utilized a genome-wide linkage analysis across 43 families. The researchers identified four chromosomal regions (2q24, 5q33, 6p12, and 12p12) associated with the condition, suggesting a complex, oligogenic inheritance pattern rather than a single-gene cause. Notably, the region on chromosome 2q24 has also been linked to autism spectrum disorders, highlighting potential shared genetic pathways between synesthesia and other neurodevelopmental conditions. These findings are significant for individuals with disabilities, as they offer insights into the neural mechanisms underlying atypical sensory experiences, which could inform future research and therapeutic approaches for related conditions - Disabled World (DW).

Introduction

A new study identifies specific chromosomal regions linked to auditory visual synesthesia, a neurological condition characterized by seeing colors in response to sounds.

Main Content

In synesthesia, which affects less than 1% of the population, stimulation of one sensory pathway results in experiences in another pathway (e.g. hearing sounds triggers colors) or in a different facet of the same pathway (e.g. reading black text trigger colors).

"Synesthesia is known to run in families but the genetics of synesthesia are not well understood," says lead study author Dr. Julian E. Asher from the Department of Genomic Medicine at Imperial College London.

Dr. Asher designed a study to look for genes linked to auditory visual synesthesia.

The research, performed as part of Dr Asher's PhD in Prof. Anthony Monaco's laboratory at the Wellcome Trust Center for Human Genetics at the University of Oxford in collaboration with Prof. Simon Baron-Cohen at the Department of Psychiatry at the University of Cambridge, involved a sophisticated genome-wide screen to search for susceptibility genes linked to auditory-visual synesthesia.

The research team identified four candidate regions linked with susceptibility to synesthesia but no support was found for an earlier theory of linkage to the X-chromosome. Although the resolution of the scan makes identifying candidate genes challenging, the researchers identified a number of interesting genes.

"The region on chromosome 2 with the strongest linkage is particularly interesting as it has been previously linked to autism," offers Dr. Asher.

"Sensory and perceptual abnormalities are common in autism spectrum conditions and synesthesia is sometimes reported as a symptom." Candidate genes associated with epilepsy, dyslexia, learning and memory are also located in the candidate regions.

The findings indicate that the genetic basis of auditory-visual synesthesia is more complex than originally believed and may be due to a combination of multiple genes subject to multiple modes of inheritance.

"This study comprises a significant step towards identifying the genetic substrates underlying synesthesia, with important implications for our understanding of the role of genes in human cognition and perception," concludes Dr. Asher.

Study Researchers

The researchers include Julian E. Asher, Wellcome Trust Center for Human Genetics, University of Oxford, Oxford, UK, University of Cambridge, Cambridge, UK; Janine A. Lamb, University of Manchester, Manchester, UK; Denise Brocklebank, Wellcome Trust Center for Human Genetics, University of Oxford, Oxford, UK; Jean-Baptiste Cazier, Wellcome Trust Center for Human Genetics, University of Oxford, Oxford, UK; Elena Maestrini, University of Bologna, Bologna, Italy; Laura Addis, Wellcome Trust Center for Human Genetics, University of Oxford, Oxford, UK; Mallika Sen, Wellcome Trust Center for Human Genetics, University of Oxford, Oxford, UK; Simon Baron-Cohen, University of Cambridge, Cambridge, UK, and Anthony P. Monaco, Wellcome Trust Center for Human Genetics, University of Oxford, Oxford, UK.

Insights, Analysis, and Developments

Attribution/Source(s): This peer reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally authored by Cell Press and published on 2009/02/05, this content may have been edited for style, clarity, or brevity.