Publication date: 7 Dec 2023
What is already known about this subject:
- The number of words a child is able to use and understand in day-to-day conversations rapidly changes from infancy to toddlerhood. It is hypothesised that genetics play a partial role in the child's language development from infancy to toddlerhood; however, to-date, the genetics that underlie language development is poorly understood.
- In this specific study, we aim to investigate the genetic factors that are linked with early life (infancy to toddler years, ~ 2 years of age) language development and later life language ability.
What this study adds
- The outcomes investigated included Expressive and Receptive Language scores assessed using the Language: Early vocabulary development (Language Development Survey data from the Raine Study Gen2-2 years follow-up). The summary results from this data was then meta-analysed with cohorts within the EAGLE consortium (N-total = 17,298 individuals with 37,913 outcomes).
- At least two distinct genetic components were found to be associated with language development, and it appears the genetic components associated with the use of language and the understanding of language are different. Another finding from this study was that the ability to use large number of words as an infant but reduced number of understanding words used by others as a toddler was correlated with risk of Attention deficit hyperactivity disorder (ADHD).
- The results from this study suggest that the genetic underlying language development is complex and dynamic. In addition, a better understanding of the genetics of language development could potentially allow a better understanding later life behaviour.