Hazen, J.L. et al. Neuron 89, 1223–1236 (2016).

It has been speculated that somatic mutations in neurons are involved in generating cellular diversity. However, single-cell genomic sequencing approaches lead to artifacts that preclude a detailed analysis of somatic mutations in postmitotic cells such as neurons. Hazen et al. created embryonic stem cells from neurons of the mouse olfactory bulb via somatic cell nuclear transfer, which resulted in sufficient cellular material for high-resolution genome sequencing. Using a bioinformatics pipeline, the researchers detected single-nucleotide variants, deletions, mobile element insertions and other mutational events. On the basis of their sample size of six cell lines, they concluded that individual neurons accumulate about 100 somatic mutations. Despite this mutational load, neurons can be reprogrammed to produce viable and fertile mice, indicating that neuronal diversity might not depend on somatic mutations.