… researchers isolated about 100 neurons from three people posthumously. The scientists took a high-level view of the entire genome—looking for large deletions and duplications of DNA called copy number variations or CNVs—and found that as many as 41 percent of neurons had at least one unique, massive CNV that arose spontaneously, meaning it wasn’t passed down from a parent. The CNVs are spread throughout the genome, the team found.
I’ve already seen work to the effect that somatic cells often have ~10x the point mutations per human generation as the germline, which is protected by a small number of divisions per generation and low levels of metabolism and transcription. It was in mitochondrial rather than nuclear DNA, but the idea is similar.
New research suggests that the amount of variance in DNA among individual cells in a person may be much higher than is normally believed. See here.
Edit: see the paper for more precise statements.
I’ve already seen work to the effect that somatic cells often have ~10x the point mutations per human generation as the germline, which is protected by a small number of divisions per generation and low levels of metabolism and transcription. It was in mitochondrial rather than nuclear DNA, but the idea is similar.