Max Planck Institute for Psycholinguistics, Nijmegen
"Identification of Candidate Genes in Multiplex Synaesthesia Families and a Large Grapheme-colour Cohort"
Synaesthesia has long been known to run in families. However, previous genetic studies have not converged on a single locus that singlehandedly explains how synaesthesia arises; rather, it appears that there are multiple genes in the human genome that contribute to building a brain that is capable of synaesthesia. We hypothesize that sequence variation in multiple genes involved in general biological processes, such as neural connectivity or sensory processing, are responsible for subtle structural and functional differences in the brains of synaesthetes, resulting in the enhanced crosstalk among senses. We are employing two complementary approaches to identify rare and common variants in the genomes of people with synaesthesia that contribute to the development of the trait. We expect that these two approaches will converge on a shared set of gene networks responsible for the underlying brain structures and processes that lead to synaesthesia. In an exome sequencing approach focused on three multiplex synaesthesia families, we have identified a set of candidate variants that are common only to relatives with the trait and thus may contribute to synaesthesia in those families. Furthermore, we are collecting a large cohort of grapheme-colour synaesthetes to test these (and other) candidate genes for association. Ultimately, in a genome-wide approach, we will assess association at markers spanning the entire human genome, comparing >1000 synaesthetes to people in the general population without synaesthesia. We study variants in genes that are unique to people with synaesthesia not only to uncover how this intriguing trait arises, but also to learn about the genetics of neural connectivity in the human developing brain.
Research Interest: My research goal is to understand the role that genetics, genomics and epigenetics play in the development of human language. I use genetic and genomic approaches to identify genes involved in language-related disease and non-disease phenotypes such as synaesthesia, specific language impairment, or familial cases of language-related deficits. By identifying the genes involved in these phenotypes and manipulating them in functional studies in the laboratory, we can elucidate the biological structures and functions in the human brain that are necessary for language development and uncover how language has evolved.