37 Genes Related to Synesthesia Identified

[BillTre]

Synesthesia is when a normal sensory input elicits sensation normally associated with a different sensory modality, for example seeing certain colors when hearing certain sounds.
I became interested in this years ago when I read "The mind of a mnemonist" by AR Luria, which described a synesthete with a photographic memory..
Unusual neuronal connections are usually thought to underlie this.
Here is a Science mag news story about a study comparing protein coding genes in synesthetes vs. non-synesthetes as lead to identifying 37 genes associated with synesthesia. Several of these genes are accosiated with neuronal development.

 

[Ygggdrasil]

Here's a link to the scientific publication:
Tilot et al. (2018) Rare variants in axonogenesis genes connect three families with sound–color synesthesia. Proc Natl Acad Sci USA Published online ahead of print, March 5, 2018. https://doi.org/10.1073/pnas.1715492115

From the Science magazine news story:

In the new work, a team led by neuroscientist Simon Fisher at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, decided to take a slightly different tack. Using a gene-sequencing technique known as whole-exome sequencing that targets only the DNA that encodes proteins, the researchers cataloged virtually every significant DNA variant in three families in which the condition is common.

I take issue with the author of the Science magazine piece saying that cataloging all protein-coding variants captures all significant DNA variant. There is much more functional non-coding DNA than protein coding DNA in the human genome. Researchers focus on the exome because it's cheaper to sequence the only the 1% of the human genome that codes for protein and because we understand better how mutations in protein coding sequences will affect their function. However, I'd be willing to bet that changes in non-coding DNA sequences also play a role. Exome sequencing strikes me as the drunkard looking for his car keys only under the lamp post (i.e. the streetlight effect).