Allelic exclusion refers to the observation that the vast majority of B cells, including naive B cells, express only one heavy chain and only one light chain. Allelic inclusion refers to the observation that a small fraction (≤1%) express two light chains, one of which is dysfunctional (e.g., autoreactive; (1)). This confounds the analysis of heavy/light chain pairing.
See also
1.
Jagota M, Hsu C, Mazumder T, Sung K, DeWitt WS, Listgarten J, et al. Learning antibody sequence constraints from allelic inclusion. Cell Systems. 2025;16(9):101368. Available from: https://doi.org/10.1016/j.cels.2025.101368