Indian scientist Dr. Saumya Jamuar recently used a novel technique called "targeted high-coverage sequencing" in order to discover hidden genetic causes of brain disorders.
The researcher at Harvard Medical School and Boston Children's Hospital, co-founder of Global Gene Corp, along with Prof. Christopher Walsh, MD, PhD, chief of Genetics and Genomics at Boston Children's Hospital, opened up new possibilities for finding genetic causes for previously mysterious neurologic and psychiatric conditions. And they were able to identify subtle somatic mutations, those affecting just a percentage of cells in patients with brain disorders.
Dr. Jamuar said that this new approach enhanced whole-genome and whole-exome sequencing and they found that 30 percent of patients with an identified mutation had a somatic mutation, 63 percent of which would have been missed on traditional testing.
Traditional methods of genetic testing are unable to detect these (somatic) mutations and hence, the true prevalence of somatic mosaicism in relation to human disease has never been quantified previously. Not every cell in the body is the same genetically, and disease-causing mutations don't necessarily affect every cell, making these mutations easy to miss even with next-generation genomic sequencing.
The study is published in The New England Journal of Medicine.