Subclone

Subclone is a term in genetics and cell biology referring to a subset of cells that descend from a single ancestral clone and share a common genetic background, while having acquired additional mutations or phenotypic differences. In laboratory settings, researchers may derive subclones from a parental cell line to study variability, test gene function, or optimize growth conditions. Subclones differ from the original clone by accumulated changes that may be genetic, epigenetic, or due to culture-induced effects.

In cancer biology, tumors often contain multiple subclones that arose through clonal evolution; these subclones may harbor distinct driver mutations and exhibit different growth rates, metastatic potential, or responses to therapy. The clonal relationships within a tumor are described as intratumor heterogeneity and can be modeled as a branching lineage where subclones derive from ancestral clones and may expand or shrink under selective pressures.

Detection and analysis commonly use sequencing approaches, including bulk sequencing to detect variant allele frequencies and single-cell sequencing to resolve individual cell lineages, along with lineage-tracing methods. Interpreting subclone data requires careful consideration of sampling bias, tumor purity, and the timing of mutations.

Understanding subclones has practical implications for treatment, prognosis, and the development of resistance. In precision oncology, therapies may target trunk mutations that are shared by all cancer cells, while acknowledging that subclonal mutations can drive resistance and relapse. In stem cell research, subclones help study differentiation pathways and genetic stability in cultured cell populations.