The feasibility of the identification and the structural and functional characterization of genes related to language seems legitimated by two groups of evidence of different though necessarily related kinds. The first group concerns that evidence that suggests that the nature of the faculty of language (FL) would be substantively innate. A second group of evidence concerns the existence of many language impairments characterized by an inherited nature. In the last few decades many different hereditary syndromes, disorders, conditions, or diseases in which only language seems to be impaired have been identified, characterized, and clinically categorized. Most relevant are the ones subsequently described: specific language impairment (SLI), dyslexia, speech-sound disorder (SSD) and other specific language impairments such as Landau-Kleffner syndrome and chromosome 22q13 deletion syndrome. Genes related to language represent one among diverse biological factors involved in the regulation of the development and functioning of the neural substrate of language.