Evolutionary study traces human blood cell origins to single-celled ancestors 700 million years ago

Researchers have published evidence that human blood cells share deep evolutionary ancestry with single-celled organisms that lived approximately 700 million years ago, predating the emergence of multicellular animal life. The study, reported by ScienceDaily on 27 May 2026, describes the reconstruction of a molecular evolutionary family tree for blood cell types, using comparative genomics to identify conserved gene expression programmes across distantly related species.

The findings suggest that the cellular machinery underlying immune function in modern vertebrates — including human immune cells — did not arise de novo in animals but instead co-opted and elaborated programmes already present in their unicellular forebears. The researchers identified transcription factor networks and gene regulatory modules shared between human haematopoietic lineages and the ancestral unicellular relatives.

The work contributes to a growing body of evolutionary cell biology research that uses large-scale comparative genomics to place animal cell types in their deep evolutionary context. Understanding the ancient origins of blood cell programmes may, in the longer term, inform research into how immune cell diversity arises during development and how it can go wrong in disease — but the study itself is a basic evolutionary genomics finding rather than a translational advance.

The primary publication details, including the journal and the lead institution, were not fully specified in the available reporting; the lede attributes the work to a team of scientists without further institutional identification.