Institute of Gerontology, Wayne State University, Detroit, MI, USA.
Department of Psychology, Wayne State University, Detroit, MI, USA.
Brain Struct Funct. 2024 Jan;229(1):223-230. doi: 10.1007/s00429-023-02716-w. Epub 2023 Oct 18.
The hippocampus (Hc) consists of cytoarchitectonically and functionally distinct subfields: dentate gyrus (DG), cornu ammonis (CA1-3), and subiculum. In adults, a single nucleotide polymorphism (rs17070145, C→ T) in KIBRA, a gene encoding the eponymous (KIdney-BRAin) protein, is associated with variability in Hc subfield volumes and episodic memory. T-allele carriers have larger DG and CA volumes and better episodic memory compared to C-homozygotes. Little is known, however, about KIBRA's role in the development of the brain and cognition. In a sample of children, adolescents, and young adults (N = 176, ages 5- 25 years), we replicated the adult association between KIBRA T-allele and larger DG and CA volumes but observed no relationship between KIBRA rs17070145 polymorphism and episodic memory. We noted, however, that a general cognitive performance index (IQ) differed across the allelic groups, with the lowest scores among T-homozygotes and the highest among C-homozygotes. Thus, in this developmental sample, KIBRA appears to have opposing effects on regional brain volume and cognition. These influences of KIBRA SNP may stem from associations between developmental reduction in brain volume and gains in cognitive performance-a hypothesis to be tested in longitudinal studies.
海马体（Hc）由细胞构筑和功能上不同的亚区组成：齿状回（DG）、角回（CA1-3）和下托。在成年人中，KIBRA 基因（编码同名蛋白的基因）中的一个单核苷酸多态性（rs17070145，C→T）与 Hc 亚区体积和情景记忆的变异性相关。与 C-纯合子相比，T 等位基因携带者的 DG 和 CA 体积更大，情景记忆更好。然而，关于 KIBRA 在大脑和认知发育中的作用知之甚少。在儿童、青少年和年轻人的样本中（N=176，年龄 5-25 岁），我们复制了成人中 KIBRA T 等位基因与更大的 DG 和 CA 体积之间的关联，但未观察到 KIBRA rs17070145 多态性与情景记忆之间的关系。然而，我们注意到，一般认知表现指数（智商）在等位基因群体中存在差异，T 纯合子的得分最低，C 纯合子的得分最高。因此，在这个发育样本中，KIBRA 似乎对区域脑体积和认知有相反的影响。KIBRA SNP 的这些影响可能源于脑体积随发育减少与认知表现提高之间的关联——这是一个有待纵向研究检验的假设。
