Learning to talk is in the genes: study

Researchers have found that genetic factors may contribute to the development of language during infancy.
Scientists from the Medical Research Council (MRC) Integrative Epidemiology Unit at the University of Bristol and colleagues have discovered a significant link between genetic changes near the ROBO2 gene and the number of words spoken by children in the early stages of language development.
Children produce words at about 10 to 15 months of age and our range of vocabulary expands as we grow - from around 50 words at 15 to 18 months, 200 words at 18 to 30 months, 14,000 words at six-years-old and then over 50,000 words by the time we leave secondary school.

The researchers found the genetic link during the ages of 15 to 18 months when toddlers typically communicate with single words only before their linguistic skills advance to two-word combinations and more complex grammatical structures.
The results, published in Nature Communications, shed further light on a specific genetic region on chromosome 3, which has been previously implicated in dyslexia and speech-related disorders.
The ROBO2 gene contains the instructions for making the ROBO2 protein. This protein directs chemicals in brain cells and other neuronal cell formations that may help infants to develop language but also to produce sounds.
The ROBO2 protein also closely interacts with other ROBO proteins that have previously been linked to problems with reading and the storage of speech sounds.

"This research helps us to better understand the genetic factors which may be involved in the early language development in healthy children, particularly at a time when children speak with single words only, and strengthens the link between ROBO proteins and a variety of linguistic skills in humans," said Dr Beate St Pourcain, who jointly led the research with Professor Davey Smith at the MRC Integrative Epidemiology Unit.