Rare Genetic Phenomenon Linked to Neuron Function and Schizophrenia - Neuroscience News

Summary: People with schizophrenia have significantly higher rates of tandem repeats in their genome, up to 7% more than in people without the mental health disorder.

Published in the journal Molecular Psychiatry, the research shows that individuals with schizophrenia had a significantly higher rate of rare tandem repeats in their genomes—7% more than individuals without schizophrenia.

And they observed that the tandem repeats were not randomly located throughout the genome; they were primarily found in genes crucial to brain function and known to be important in schizophrenia, according to previous studies.

In their current study, Szatkiewicz and her team looked at the entire genomes of 2,100 individuals to find tandem repeats that looked abnormally long and were unique or rare.

Because all participants provided access to their medical records, the team was able to compare these long and rare repeat DNA sequence samples from people who had schizophrenia versus samples from people in the study who didn’t.

This allowed the researchers to determine which of these tandem repeats may be involved with the development of schizophrenia.

Using gene network analysis, the authors of this study demonstrated that genes with rare tandem repeats found in schizophrenia primarily impact synaptic and neuronal signaling functions.

The Szatkiewicz findings were replicated in the Canadian investigation, indicating that this newly discovered link between tandem repeats and schizophrenia is quite strong.

“Rare tandem repeat expansions associate with genes involved in synaptic and neuronal signaling functions in schizophrenia” by Jia Wen et al.

Rare tandem repeat expansions associate with genes involved in synaptic and neuronal signaling functions in schizophrenia.

Using genome sequence data from 1154 Swedish schizophrenia cases and 934 ancestry-matched population controls, we have detected genome-wide rare (<0.1% population frequency) TREs that have motifs with a length of 2–20 base pairs

We find that the proportion of individuals carrying rare TREs is significantly higher in the schizophrenia group

There is a significantly higher burden of rare TREs in schizophrenia cases than in controls in genic regions, particularly in postsynaptic genes, in genes overlapping brain expression quantitative trait loci, and in brain-expressed genes that are differentially expressed between schizophrenia cases and controls

Our results support the involvement of rare TREs in schizophrenia etiology