A New Find in Autism Research

Suzette Rodriguez

Autism is a serious disorder affecting an average of 1 in 110 children today¹ and currently scientists are studying the disorder in varying approaches including determining its prevalence in U.S. populations, looking into genetic databases, as well as relating its existence with other medical conditions (such as Down Syndrome)². In a paper published in Nature researchers compared abnormal gene expression and the prevalence of genetic markers in different regions of autistic and normal patients’ brains. The results of the study differs from the hypothesis that many genetic and spontaneous mutations are the source of autism³, since they have found that there are some common patterns in the gene expression in the brains of autistic patients⁴. These ideas are not necessarily mutually exclusive, except this research encourages looking into these patterns to find more commonalities in gene expression of autistic patients and thus have some direction to follow when doing autism research.

Researchers tend to focus on comparing DNA sequences of autistic and control patients, but in this study they focus on comparing mRNA sequences instead. Looking for abnormalities in gene expression, researchers have found that autistic patients lack the specialized differentiation of the frontal and temporal lobes. Specialized differentiation refers to each section of the brain pertaining to a specialized function of the body such as speech processing, motor skills, and somatosensory functions. Two-thirds of the autistic patients in the study have been shown to have homogeneity instead of specialized differentiation in gene expression when compared to normal patients. This result suggests that the specialization of these lobes in autistic patients was impaired at some point during their development. This find in autism research may help future studies to look for more similarities in gene expression.

Two gene networks have been studied with one involving the gene splicer, A2BP1. A2BP1 is downregulated in autistic patients which results in incorrectly splicing genes involved with synaptic functioning. The second network involves nerve cell markers, ADFP and IFITF2, which are involved with the expression of immune and inflammatory genes. The study also included a genome-wide scan comparing the occurrence of A2BP1 in the gene networks of other patients. A2BP1 was found to be common in autistic patients and the nerve markers are thought to be secondary effects.

The degree of autism varies greatly on the spectrum from one patient to another. These common patterns are providing hope for scientists to find common therapies to administer to autistic patients.  The study on autism continues since the cause of this disorder is still unknown, but scientists are getting closer to finding more information on the commonalities among autistic patients.

¹Centers for Disease Control and Prevention. <http://www.cdc.gov/ncbddd/features/counting-autism.html.> June 2, 2011. 

²Centers for Disease Control and Prevention. <http://www.cdc.gov/ncbddd/autism/research.html.> June 2, 2011.

³Sebat J, Lakshmi B, et al: “Strong association of de novo copy number mutations with autism.” Science. 2007 Apr 20: 316(5823):445-9.

⁴Voineagu, I., et al. “Transcriptomic analysis of autistic brain reveals convergent molecular pathology.” Nature, doi: 10.1038/nature10110, 2011.