Grey Skulls

Embryos develop in a series of careful changes. One early stage involves neural crest cells migrating to different parts of the embryo, where they differentiate or specialise into the patterns that define the body. Each of these steps relies on 'switching on' of genes – gene expression – in the right cells at the right time. Here early bone cells called osteoblasts shape the normal skull of a developing mouse at the top, while the skull of the lower mouse is formed differently. The lower skull lacks a gene called Eed, which helps to guide gene expression inside osteoblast cells. Removing Eed interferes with epigenetic controls – chemical groups attached to the DNA which change access to certain genes. In humans and mice, epigenetic patterns can be inherited, raising new questions about how development might be shaped at delicate early stages of life.

Written by John Ankers

John Ankers

Writer

A former researcher in systems biology, John is now an online biology tutor and professional coach supporting the wellbeing of scientists and NHS professionals. He's writing, too, of course.

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• Image from work by Tim Casey-Clyde and colleagues
• Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
• Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)
• Published in eLife, December 2025