High Transposable Element Content in Strong-Association Autism-Risk Genes

Background: Rates of mutation vary by gene, reflective of different trends in overall stability. These variations in stability are due to a number of factors, one of which relates to overall transposable element (TE) content within the gene.

Objectives: We have elected to study rates of TE content across high-risk autism-related genes as compared to randomized controls in order to gauge one aspect of genetic instability in these genes.

Methods: Our autism data were collected using the AutismKB database, while matched numers of controls were generated using a random gene generator. The database, TranspoGene, provided listings of TE content for our study. Due to the nature of our distributions, a nonparametric Kuiper test was utilized as well as logistic regression.

Results: We found that autism genes housed significantly greater TE content than randomized controls and that for every doubling of TE content, a given gene was 17% more likely to be associated with our autism group.

Conclusions: Our results suggest that autism genes may share a relative instability in relation to their TE content, leading to more frequent mutations. While many studies have attempted to address functional commonalities amongst autism-related genes, ours is the first study which seeks commonality at the level of the gene rather than its gene product. In understanding how and when such mutations may arise, we may better understand what roles they play in autism's etiology.