Diverse mutational landscapes in human lymphocytes

Dataset ID Technology Samples
EGAD00001008107 HiSeq X Ten 717

Dataset Description

A lymphocyte suffers many threats to its genome, including programmed mutation during differentiation, antigen-driven proliferation and residency in diverse microenvironments. After developing protocols for single-cell lymphocyte expansions, we sequenced whole genomes from 717 normal naive and memory B and T lymphocytes and hematopoietic stem cells. All lymphocyte subsets carried more point mutations and structural variants than haematopoietic stem cells – the extra mutations were mostly acquired during differentiation, with burdens higher in memory than naive lymphocytes, although T cells also had a higher rate of mutation accumulation throughout life. Off-target effects of immunological diversification accounted for most of the additional differentiation-associated mutations in lymphocytes. Memory B cells acquired, on average, 18 off-target mutations genome-wide for every one on-target IGV mutation during the germinal centre reaction. Structural variation was 16-fold higher in lymphocytes than stem cells, with ~15% of deletions being attributable to off-target RAG activity. Mutational processes associated with ultraviolet light exposure and other sporadic mutational processes generated hundreds to thousands of mutations in some memory lymphocytes. The mutation burden and signatures of normal B lymphocytes were broadly comparable to those seen in many B-cell cancers, suggesting that malignant transformation of lymphocytes arises from the same mutational processes active across normal ontogeny. The mutational landscape of normal lymphocytes chronicles the off-target effects of programmed genome engineering during immunological diversification and the consequences of ... (Show More)

Data Use Conditions


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Label Code Version Modifier
general research use DUO:0000042 2021-02-23
institution specific restriction DUO:0000028 2021-02-23
publication required DUO:0000019 2021-02-23
user specific restriction DUO:0000026 2021-02-23