How Does Germline Regenerate?

A concise primer that complicates a convenient truth in biologyâ?¿the divide between germ and somatic cellsâ?¿with far-reaching ethical and public policy ramifications.   Scientists have long held that we have two kinds of cellsâ?¿germ and soma. Make a change to germ cellsâ?¿say using genome editingâ?¿and that change will appear in the cells of future generations. Somatic cells are â??safeâ?? after such tampering; modify your skin cells, and your future childrenâ?¿s skin cells will never know. And, while germ cells can give rise to new generations (including all of the somatic cells in a body), somatic cells can never become germ cells. How did scientists discover this relationship and distinction between somatic and germ cellsâ?¿the so-called Weismann Barrierâ?¿and does it actually exist? Can somatic cells become germ cells in the way germ cells become somatic cells? That is, can germ cells regenerate from somatic cells even though conventional wisdom denies this possibility? Covering research from the late nineteenth century to the 2020s, historian and philosopher of science Kate MacCord explores how scientists came to understand and accept the dubious concept of the Weismann Barrier and what profound implications this convenient assumption has for research and policy, from genome editing to stem cell research, and much more.