<P> Several cases of developmental verbal dyspraxia in humans have been linked to mutations in the FOXP2 gene . Such individuals have little or no cognitive handicaps but are unable to correctly perform the coordinated movements required for speech . fMRI analysis of these individuals performing silent verb generation and spoken word repetition tasks showed underactivation of Broca's area and the putamen, brain centers thought to be involved in language tasks . Because of this, FOXP2 has been dubbed the "language gene". People with this mutation also experience symptoms not related to language (not surprisingly, as FOXP2 is known to affect development in other parts of the body as well). Scientists have also looked for associations between FOXP2 and autism, and both positive and negative findings have been reported . </P> <P> There is some evidence that the linguistic impairments associated with a mutation of the FOXP2 gene are not simply the result of a fundamental deficit in motor control . For examples, the impairments include difficulties in comprehension . Brain imaging of affected individuals indicates functional abnormalities in language - related cortical and basal / ganglia regions, demonstrating that the problems extend beyond the motor system . </P> <P> The FOXP2 gene is highly conserved in mammals . Human gene differs from non-human primates by the substitution of two amino acids, threonine to asparagine substitution at position 303 (T303N) and asparagine to serine substitution at position 325 (N325S). In mice it differs from that of humans by three substitutions, and in zebra finch by seven amino acids . One of the two amino acid difference between human and chimps also arose independently in carnivores and bats . Similar FOXP2 proteins can be found in songbirds, fish, and reptiles such as alligators . </P> <P> DNA sampling from Homo neanderthalensis bones indicates that their FOXP2 gene is a little different, though largely similar to those of Homo sapiens (i.e. humans). </P>

The foxp2 sequences of mice were most different from those of