Mutations accumulate in the genome of every cell of the body throughout life, causing cancer and other genetic diseases. Almost all of these mosaic mutations begin as nucleotide mismatches or damage in only one of the two strands of the DNA prior to becoming double-strand mutations if unrepaired or misrepaired. However, current DNA sequencing technologies cannot resolve these initial single-strand events from which mutations originate. This talk will present a novel single-molecule, long-read sequencing method that achieves single-molecule fidelity for single-base substitutions when present in either one or both strands of the DNA. It also detects single-strand cytosine deamination events, a common type of DNA damage. Since the double-strand DNA mutations interrogated by prior studies are only the endpoint of the mutation process, this approach to detect the initiating single-strand events at single-molecule resolution will enable new studies of how mutations arise in healthy tissues and in cancer.

Learning Objectives:

1. Describe the key features of aging-related somatic mutation in the body.

2. Discuss the limitations of standard DNA sequencing in studying somatic mutation.

3. Evaluate the principles of new DNA sequencing technologies with higher accuracy that can detect aging-related somatic mutations in healthy tissues.