Researchers are in the process of studying singing mice to gain insight into their unique behavior, in the hopes of identifying genes that cause speech disorders in humans.
The research team from the Texas Advanced Computing Center (TACC) at The University of Texas in Austin are analyzing the genes of the singing mice (scotinomys teguina), which hail from forests in the mountains of Costa Rica.
They produce a string of high-pitched chirps of up to 20 squeaks per second, which sounds similar to a birdsong, in order to communicate with other mice. However, the researchers say that unlike birds, the mice sing a song in only one note.
In this latest study, the researchers have focused on a particular gene that makes up the components of the mouse song - FOXP2.
The researchers say that this gene is of interest as it is the only gene that has been found to be involved directly in human speech disorders.
FOXP2 gene 'may interact with DNA'
The FOXP2 gene in humans has been linked to many speech problems. The gene plays a role of a "transcription factor," which helps control the expression of other genes.
When a FOXP2 gene is mutated, this causes a decline in gene expression that can lead to numerous speech problems, such as stuttering.
The researchers say this gene is very similar between singing mice, lab mice and humans. Therefore, the aim of this study is to identify parts of the gene that contribute to the mouse song and find evidence of "natural selection," away from gene mutations.
For this study, the researchers have been playing recordings to the singing mice of their own species alongside other recognizable species, to observe the gene expression patterns.
Lauren O'Connell, a postdoctoral researcher at TACC, says:
"We found that when an animal hears a song from the same species, these neurons that carry FOXP2 become activated. So we think that FOXP2 may play a role in integrating that information."
Steven Phelps, researcher at the University of Texas and lead researcher in the project, says that by learning what activates the FOXP2 gene and what genes are activated by it, it may show how surrounding conditions could affect gene expression, as well as which genes are important and involved in the process.
"We ask two things, whether there are sequence changes in the DNA that are associated with the elaboration of the song and whether particular elements seem to be interacting with FOXP2 more," says Phelps.
"That gives us leads into what role FOXP2 might play into the elaboration of vocalization."
To understand how FOXP2 interacts with DNA in order to regulate the function of other genes, the researchers have used two "supercomputers," which read small fragments of overlapping DNA so the full sequence can be deducted.
Genetic cause of speech disorders could be identified
This continued research, according to Phelps, will help to find out more about the link between FOXP2 and the singing mice, therefore generating more information about how the gene affects speech disorders in humans.
The researchers say that if the sequences of DNA that interact with FOXP2 can be identified alongside other genes linked to gene function, it might be possible to identify a "causal sequence."
"When people do genome-wide association studies in humans, the genetic variation tends to occur in huge blocks," Phelps adds.
"So if you get some DNA sequence that predicts a phenotype, like risk for autism, it is very hard to know what aspect in this very long stretch of DNA is actually important for that."