[Problematic aspects of the genetic analysis of the specific disorders of the language: FOXP2 as paradigm]

Genetic analysis of specific language disorders is of major interest for both clinical research and linguistic theory. However, the results of this analysis almost always do not show any univocal and compulsory relationships between particular gene mutations and particular disorders or a casual link between the genotype and the phenotype.

This paper will review this type of evidence (referring to the «language gene»FOXP2 as a leading example, where possible), try to suggest plausible reasons for such a perplexing output, and ultimately discuss if such reasons really explain the genuine aetiology of these conditions.

The key to disentangle and understand the puzzling scenario emerging from the genetic analysis of specific language disorders is to pay attention to the actual role played by genes during ontogeny and, in particular, to the way in which developmental processes are actually regulated: genes are not direct causal agents regarding the emergence of impaired or wild phenotypes, but just one among the diverse types of regulatory factors involved.

When such a complex role as well as development models less focused on the genes are considered, the way in which genetic mutations really contribute to the emergence of these cognitive disorders is quite satisfactorily explained.