A team of researchers at the University of Texas Medical Branch and Medical University of South Carolina has solved a mystery associated with early gene shutdowns in children – a disorder that afflicts some individuals and may contribute to autism, schizophrenia and other mental illnesses. In their paper published in Proceedings of the National Academy of Sciences, the group describes their study of 635 young women who are members of a Zara, a Minneapolis-based woman’s group that provides resources and services for mothers and their infants.

Prior research suggests that early gene initiation or suppression, or deletion in early child development, may cause autism, schizophrenia, autism-like disorders and other developmental disorders. However,’s study is the first to use the Swedish synchrotron emission tomography (sc-EM) technique to image twins, non-twin siblings and a third-generation, unaffected unblinded control cohort, and to ascertain which deep-brain regions, the brains and blood vessels of people with autism, schizophrenia, bipolar disorder or other forms of mental illness are most implicated in early gene shutdown.

Tammy Davidson, lecturer in the University’s Center for Human Genetics and Environment and co-author on the paper, explains that the team use-deletion images to measure changes in the connections between brain regions and the blood-brain barrier, which acts as a cellular barrier that helps maintain a healthy atmosphere in the central nervous system.

Davidson and her co-authors also explored neuropsychological and laboratory functioning measures, but focused first on gene expression measures: measures the rate of RNA binding to DNA, a DNA-binding compound in cells, and expression of genes that encode proteins involved in gene functions.

The researchers report that measuring RNA binding to the DNA binding protein required for gene expression were present in 13% of the children with autism; 34% of the control subjects; and 62% of the twin sisters. RNA binding to the brain region involved in forming the cerebral cortex was 34 percentage points higher in the babies with autism and 60% of the control twins. On the other hand, expression of genes involved in neurotransmission, a process in the brain that is linked to mental function, was two percentage points higher in the twins with autism and 59% of those in the control group.

Davidson notes that her team’s findings suggest that repression at various neural, neuronal and other important brain regions may be related to individual differences in gene expression. “We do not know yet how different regions lie in time when gene expression is not detectable,” she says.