Genetics: The basis for baby talk

A new gene associated with early language acquisition has been identified in infants, reports a study published online this week in Nature Communications. These findings could lead to a better understanding of the pathways involved in speech development and language-related disorders, such as dyslexia.

Children speak their first words at about 10 to 15 months of age and their spoken vocabulary and grammatical complexity increases rapidly soon afterwards. Previous studies in twins at the age of 24 months, when two-word combinations are typically expressed, demonstrate that this acquired vocabulary is heritable.

Beate St Pourcain and colleagues used language proficiency data from more than 10,000 infants aged between 15 and 30 months to look for possible associations between vocabulary scores and genetic variation. They identify a specific region of the genome that is significantly associated with the acquisition of single words in the early phases of development, but not in later stages when two-word combinations have developed.

This newly identified region is located near a gene called ROBO2, encoding a protein with a key role in neural processes, and resides within a specific part of chromosome 3, which has been previously linked to dyslexia and speech-related disorders.