London: More than 50 percent of sporadic cases of schizophrenia are caused by new, or “de novo,” protein-altering mutations—genetic errors that are present in patients but not in their parents, a new research has shown.
A group led by Maria Karayiorgou, MD, and Joseph A. Gogos, MD, PhD, examined the genomes of patients with schizophrenia and their families, as well as healthy control groups. All were from the genetically isolated, European-descent Afrikaner population of South Africa.
They found 40 mutations, all from different genes and most of them protein-altering.
The results point the way to finding more, perhaps even hundreds, of mutations that contribute to the genetics of schizophrenia—a necessary step toward understanding how the disease develops, the researchers said.
“Identification of these damaging de novo mutations has fundamentally transformed our understanding of the genetic basis of schizophrenia,” says Bin Xu, PhD, assistant professor of clinical neurobiology at Columbia University Medical Center and first author of the study.
“The fact that the mutations are all from different genes,” says Karayiorgou, “is particularly fascinating. It suggests that many more mutations than we suspected may contribute to schizophrenia. This is probably because of the complexity of the neural circuits that are affected by the disease; many genes are needed for their development and function,” she added.
The study was recently published online in Nature Genetics.