Researchers at the RIKEN Cluster for Pioneering Research in Japan report that Kleefstra syndrome can be reversed after birth in a mouse model of the disease. Kleefstra syndrome is a genetic disorder that leads to intellectual disability. The study was published in the scientific journal iScience.
The study included a series of experiments led by Yoichi Shinkai that showed that postnatal treatment resulted in improved symptoms, both in the brain and in behaviour. Researchers usually collect two good copies of most genes, one from each parent. In Kleefstra syndrome, one copy of the EHMT1 gene is mutated or missing. This leads to half the normal amount of GLP, a protein whose job is to control genes related to brain development through a process called H3K9 methylation. Without the exact amount of GLP, H3K9 methylation is also reduced, and the connections between neurons in the brain do not develop normally.
The additional requirement of GLP might be an effective treatment, the researchers performed a series of experiments in mice that were engineered to have only one good copy of the EHMT1 gene. The brains of these mice show characteristics of the human condition, including 40% less GLP and 30% less H3K9 methylation.