Since the groups had the same memory performance, the results were explained as indicating that non-carriers needed to compensate for their poorer memory function with increased activation of the hippocampus in order to reach the same level of performance as T carriers. Increased activation in the hippocampus is strongly associated with positive aspects of the memory function, and with other genes related to memory the opposite has been observed: increased hippocampus activation in carriers of a gene variant that is associated with better memory (e.g. Hariri et al., 2003). In those cases a reasonable explanation has been that the gene is important for memory via a favorable effect on the hippocampus function.
Improved memory performance in carriers of the KIBRA T allele has been verified in several subsequent studies (e.g. Bates et. al., 2009, Preuschhof et al., 2010), but since the 2006 Science article, this is the first to study KIBRA in relation to brain activation.
|Contact: Bertil Born|
Swedish Research Council