The role of human unique insertions in neurodevelopmental evolution and disease
Fall 2021 Graduate Student Award in Brain Sciences
How did humans diverge in evolution from close relatives like chimpanzees and gain unique neurological traits, such as advanced cognitive capabilities and susceptibility to certain mental illnesses? Since the chimp genome is 98% identical to ours, researchers are filtering through the 2% of the genome unique to humans for answers. Insertions, or places where humans have DNA sequences that chimps lack, have been understudied. However, because the insertions contain novel sequences and exhibit more extreme divergence between humans and chimps, I hypothesize that insertions not only drove human evolution, but also continue to be important to human health, because individuals that carry different variants of the insertion may be more susceptible to certain diseases. With the advent of new technologies, I was able to begin my study by compiling a preliminary list of 23,660 unique human insertions. Many of them are likely to function in brain development. For example, I am currently focused on an insertion in a region that is known to be associated with Alzheimer’s disease. Learning about this insertion and others will help us understand what makes us human and possibly advance clinical practices.