FOXP2 Gene

FOXP2 Mutation

The FOXP2 gene is thought to have an important role in speech. A link was found between the gene and speech disorders when researchers studied a family where about half of them had severe difficulty speaking. It was later discovered that they suffered from a point mutation on FOXP2 gene. A point mutation occurs when one base pair is altered or deleted. The researchers used the fact that previous brain imaging tests like PET scans and MRIs were performed on the affected family and a control group showed that the affected family did have brain abnormalities to compare their research with. The purpose of this experiment was to see if there was a correlation between FOXP2 expression during brain development and speech pathologies.

The researchers looked at FOXP2 expression in mouse and human embryos. Human embryos were only used in there early gestational stage while mouse embryos were used to look at later stages as well as earlier stages. The researchers used hybridization techniques where they dissected fetuses and embryos at different stages of development and put them through various chemical processes where they were fixed to microscope slides. PCR was used to amplify two different regions of the FOXP2 gene.

The researchers found that in early development, the gene is expressed in multiple parts of the brain, but as the brain matures FOXP2 is expressed in more specific areas of the brain such as the caudate nucleus. The caudate nucleus is part of the brain associated with motor function and memory. During the development of the central nervous system, FOXP2 was transcribed in the motor areas of the brain. The central nervous system is made up of the brain and spinal cord. The researcher predicted that a mutation to the gene at this point could account for why it is difficult for the affected family to move their mouths to form words. Another thing that was found was the expression of the FOXP2 gene was expressed very similarly in mice and humans. There was no specific place found in the brain where FOXP2 was just expressed in humans. In comparison to the different brain scans where the caudate nucleus was overactive during word repetition tasks, this experiment found the FOXP2 gene to be expressed in the caudate nucleus. Overall, these experiments were in agreement with prior research on the FOXP2 gene. To continue work with the FOXP2 gene the researchers suggested using mice with a mutated FOXP2 gene.

I personally thought that the link between FOXP2 and speech was the most interesting part the article. I was fascinated by the family where some. Before writing this I only knew a little bit about the FOXP2 gene. The only thing I knew was that it was related to speech, now I understand that there is much more involved and that the gene works with many parts of the brain. I also think it would be interesting to compare a mutated mouse FOXP2 gene to a mutated human one and see the difference in brain structure and what happens in the motor areas of the brains.

Katie Mireles

References:

Copp, A. J., Fisher, S. F., Gerrelli, D., Lai, C., & Monaco, A. P. (2003). Foxp2 expression during brain development coincides with adult sites of pathology in a severe speech and language disorder. Brain Journal of Neurology, 126(11). Retrieved from http://brain.oxfordjournals.org/content/126/11/2455/full.

(2011). Coordination by nerve signaling. In Introduction to biology 102 (pp. 222-245). McGrawHill.