There are lots of different aspects to human communication, including speech, facial expressions and body movements / gestures. There have been some exciting discoveries about genetic contributions to communicative behaviours. A famous example is the gene FOXP2, whose role in language was discovered in humans through studies with a family known as the “KE family”. Several members of that family have difficulties producing speech, and those people were found to have a different structure to their FOXP2 gene than is typically found in humans. Other studies have shown a role for FOXP2 in how songbirds learn their songs, and even how mice produce their vocalizations. So, it definitely has an important role in communication, but we don’t yet know the precise relationship between this gene and behaviour, and there are many other genes at work that are also relevant for speech.