pangenes

Pangenes, or pangenesis, is a historical hypothesis of inheritance proposed by Charles Darwin in 1868 to explain how traits pass from parents to offspring. The theory posits that tiny particles called gemmules or pangenes are produced by cells throughout the body. These particles travel through the bloodstream to the reproductive organs, where they aggregate in developing gametes and are transmitted to the next generation. Each tissue contributes its own pangenes, carrying information about the organism’s traits and experiences.

Darwin suggested that inheritance is a composite of contributions from all parts of the body, and that acquired modifications could be inherited through these gemmules. He envisioned that offspring would reflect a blend of parental contributions, with gemmules potentially reconstituting in new organisms.

The idea faced significant criticism and was largely abandoned with the rise of Mendelian genetics and modern germline theory. August Weismann’s germ plasm theory, which posited that inheritance occurs exclusively through germ cells and that somatic changes do not influence gametes, challenged pangenesis. Experimental evidence increasingly supported discrete hereditary units rather than somatic-derived particles.

Today pangenesis is understood as a historical, now-discredited attempt to explain heredity. It is frequently cited in discussions of the history of genetics and as a cautionary example of how scientific hypotheses can be superseded by empirical evidence. Some modern concepts, such as epigenetic inheritance, explore how gene expression can be influenced by life experiences, but these ideas are not explanations of pangenes and do not align with the original mechanism Darwin proposed.