Genetics: Study links MET gene to emotion recognition
A well-known autism risk gene, MET, is involved in the ability to recognize emotions from facial expressions, according to a study published 27 April in PLoS ONE1.
In the new study, researchers gave 182 healthy adults the Mayer-Salovey-Caruso Emotional Intelligence Test, in which participants try to identify emotions — happiness, sadness, surprise, fear or excitement — depicted on pictures of faces.
The researchers also screened the participants' DNA for common variations at a particular spot in the MET gene. At a location called rs2237717, individuals carry one of three different allele pairings: CT, TT or CC. Participants with the CT genotype perform better on this test than do those with TT, the study found.
MET is known to be needed for the addition of a phosphate group to a gene called AKT, which has been linked to schizophrenia. A 2008 study found that people carrying a certain variant of AKT have impaired executive function, perform slower on intelligence tests and have lower verbal ability than do those with other variants of the gene3.
The new study also showed that certain combinations of common variants in MET and AKT are associated with better performance scores on the emotion recognition test than other variant combinations.
Taken together, the results suggest that MET is involved in the brain's processing of facial emotions, a skill that often goes awry in individuals with autism.
However, the MET variation linked to autism does not seem to have any influence over emotion perception. This may be because the new study recruited Han Chinese participants from Taiwan, whereas previous studies relied mostly on Caucasians from Italy and the U.S.
1: Lin M.T. et al. PLoS One 7, e36143 (2012) PubMed
2: Campbell D.B. et al. Proc. Natl. Acad. Sci. U. S. A. 103, 16834-16839 (2006) PubMed
3: Tan H.Y. et al. J. Clin. Invest. 118, 2200-2208 (2008) PubMed