• A study of over 70,000 infants identified 11 genetic markers influencing the age at which babies start walking independently.
• Genetics accounts for approximately 25% of the variability in when children begin to walk, according to the study.
• The identified genetic factors are partly the same as those influencing brain development, educational attainment, and ADHD risk.

A new study from the University of Surrey, in collaboration with scientists in the UK, Netherlands, and Norway, has found that genetics plays a significant role in determining when infants begin to walk. The research, published in *Nature Human Behaviour*, analyzed the genetic information of over 70,000 infants and identified 11 genetic markers influencing walking age. This milestone, typically occurring between 8 and 24 months, is influenced by both genetic and environmental factors, with the study suggesting a link between walking age and brain development, educational attainment, and the likelihood of developing ADHD.

• What: A genome-wide association study (GWAS) meta-analysis identified 11 independent genome-wide significant loci associated with the age at which infants begin to walk independently.
• Who: The study was led by scientists at the University of Surrey, with collaboration from researchers in the UK, Netherlands, and Norway. Key individuals include Professor Angelica Ronald and Dr. Anna Gui.
• When: The study was published in May 2025. Data was collected from infants of European ancestry.
• Where: The research involved data from cohorts in the UK, Netherlands, and Norway.

This research provides novel insights into the genetic basis of a key developmental milestone: walking. The discovery of 11 genetic markers associated with walking age opens new avenues for understanding the biological mechanisms underlying motor development. The finding that these genetic factors are linked to brain development, educational attainment, and ADHD risk suggests a complex interplay between genes and various aspects of human development. While the study acknowledges the role of environmental factors, it underscores the significant contribution of genetics to the variability in walking age.

Until now, we didn't understand what causes the wide differences between children in when they take their first step. Parents might often worry that walking early or late is a bad sign or that they have done something wrong. We see that genetics play a considerable role in influencing the timing of this milestone.

We hope these new genetic findings can advance fundamental understanding about the causes of walking and be used to better support children with motor disorders and learning disabilities. While parents should still see their GP if they are concerned, a slightly later start is not always a sign of problems. There is a lot of variety in when children take their first step on their own.

The University of Surrey-led study provides compelling evidence for the genetic influence on infant walking age, identifying specific genetic markers and their links to other developmental traits. These findings advance our understanding of motor development and highlight the importance of considering both genetic and environmental factors. While the research offers valuable insights, further investigation is needed to explore the interplay between these genetic markers and various developmental outcomes, which may have implications for supporting children with motor disorders and learning disabilities.