KIBRA gene variants are associated with episodic memory performance in subjective memory complaints.

The KIBRA gene encodes a cytoplasmatic protein, a member of the signal transduction protein family, expressed mainly in the brain. Recent studies have implicated the involvement of a genetic variation in the KIBRA gene (T allele) in human memory in normal subjects and in the risk of developing Alzheimer's disease (AD). We report here the distribution of the KIBRA genetic variant and the Apolipoprotein E (ApoE) epsilon4 allele and their association with neuropsychological measures in older adults reporting problems with everyday memory (subjective memory complaints, SMC). We found that SMC subjects with the CT/TT genotype performed more poorly than those with the CC genotype on long-term memory tests. Thus, in our opinion, these data suggest that the KIBRA genotype could affect memory performance in a different way in those that complain of memory deficits compared to those that do not.