Up until now, various researches conducted to better explain autism have principally targeted the neurons and neuronal development in children. While, these studies have identified various genes which are involved in autism, they have been unsuccessful at fully comprehending the said disease. However there may be more factors at work as the researchers of the Stanford University explain.
“Until now, we’ve suspected that autism could be the result of defects in the neurons themselves. Now it appears that the oligodendrocytes can contribute to the problem by inhibiting neuronal signaling through poor cellular differentiation and myelination,” said Michael Snyder who is a professor in Genetics and the senior author of the study.
Researchers have tried a different approach at unravelling the disease. They turned to the human interactome which basically is protein interactions within the brain at molecular level. The researchers analysed the data about the human protein interactome and mapped out proteins into modules according to their functions and interactions. They found that most of the autism related genes were clustered in one module. What holds more interest is that, although, almost half of these genes were expressed throughout the brain, the remaining half were expressed in the corpus callosum. The corpus callosum is what bridges connections between the two hemispheres of the brain and is significantly reduced among autism patients.
They confirmed their tests on people with autism and saw that almost 38 genes within the module showed noteworthy mutations. Taking it one step further, they also analyzed frozen post-mortem samples of brain for confirmation.
“This is our first glimpse of autism’s underlying biological framework, and it implicates a cell type and region of the brain that have not been extensively studied in this disease,” said the researchers, commenting on the fact that focus should not be reserved just for neurons but other cell types involved in the brain such as the oligodendrocytes should be considered too.
Not all autism cases are the same because the disease is highly heterogeneous. But in cases, where the problem stems from the corpus callosum instead of neurons, researchers say that finding the correct cause and targeting it for treatment may provide better results.