Chicken and egg mystery solved in new DNA book for younger readers

The age-old question of which came first – the chicken or the egg – has an answer now thanks to a new book for children that explores the role of DNA as the fundamental building block of life.

Written by two expert geneticists working at the University of Leicester and the University Hospitals of Leicester NHS Trust, What is DNA? explains how the DNA chemical works inside our bodies, how life began on Earth and how all living things are connected by their DNA. 

Aimed at readers aged eight and above, the book explores topics such as why some of us really don’t like Brussels sprouts – and why some of us love them! – and how DNA can solve crimes and make our lives better. Illustrated with hilarious cartoons by Nigel Baines, it provides a humorous introduction to DNA and genetics for the budding scientist.

Silly but accessible, the geneticists attempt to show how DNA can provide answers to children’s most pressing questions about the world – such as, whether it was the chicken or the egg that came first.

Co-author Professor Julian Barwell, Honorary Professor in Genomic Medicine at the University of Leicester, said: “Genes provide the instruction manual to build and maintain the body. Small changes occur in these as they are passed from generation to generation and so your DNA acts as a marker of time as well as controlling how our bodies are constructed. The egg for what we now call a chicken therefore came from two parents that were slightly different but where a new gene change was added and then passed onto the next generation – so the egg came first, but not from a chicken. By looking at DNA closely we can work out that a chicken's ancestors were actually dinosaurs and chickens are closer to dinosaurs than crocodiles are!

“We wanted a fun approach to learning about the role of DNA in understanding life on Earth, our link to nature and the fact that our DNA is a biological clock as well as a code. We were inspired by seeing how well people connected to questions about ginger hair and Brussels sprouts! So we wanted to tackle this topic by asking fun questions, like ‘is Granddad a dinosaur?’ or ‘are we 50% a mushroom?’. 

“This goes much further than standard genetics books by covering all inheritance patterns, the beginning of life and evolution, viral genetics and behavioural genetics. We are all linked to living things and nature through our DNA which is a code but also a biological clock to the past.”

Co-author Dr Neeta Lakhani, Consultant in Clinical Genetics at the University Hospitals of Leicester NHS Trust and a graduate of the University of Leicester, said: “Recent events, particularly the COVID-19 pandemic and the development of vaccines, have sparked curiosity in genetics among children, prompting questions about our similarities and differences. Exploring DNA in a children's book not only educates them about their biological makeup but also highlights how cutting-edge science, like the COVID vaccine, impacts our daily lives, all in a very fun way! 

“Introducing scientific concepts early, such as understanding who we are and how we are made, is incredibly important. Whether young or old, understanding DNA is the foundational step in comprehending our identity and connection to the world around us.”