The FOXP2 gene was thereafter used to examine the history of language evolution through the understanding and analysis of language impairments. That said, there remains two issues unresolved; that is, the link between FOXP2 and human languages is still inconclusive.

The discovery of FOXP2 was through the analysis of the DVD, which itself is widely considered to be an umbrella term for several other language disorders. The KE family would certainly not be affected by the entire array of language disorders, and thus the attempt to link the FOXP2 to human languages may be problematic. Secondly, there is also a lack of complete understanding of the FOXP2, and its function, especially pertaining to the acquisition and management of human languages. FOXP2, being a transcription gene, activates a number of other genes instead of operating within a structure of its own, also makes it difficult to attribute its effects on other genes, and its own functions to the human language. Therefore, even when it is popular to sell the theory that the FOXP2 can potentially be linked to the human-ape differences and not just language evolution, it is still commonly agreed that until it can be clearly established how the FOXP2 can be turned on and off, it is premature to claim the FOXP2 has direct links with language. (Bickerton, 2007).