bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/070409

Association of AKAP6 and MIR2113 with cognitive performance in a population based sample of older adults

Shea Andrews·Debjani Das·Kaarin J Anstey·Simon Easteal
View original source ↗Export metadata ↓

Abstract

Genetic factors make a substantial contribution to inter-individual variability in cognitive function. A recent meta-analysis of genome-wide association studies identified two loci, AKAP6 and MIR2113 that are associated with general cognitive function. Here, we extend this previous research by investigating the association of MIR2113 and AKAP6 with baseline and longitudinal nonlinear change across a broad spectrum of cognitive domains in community-based cohort of 1,570 older adults without dementia. Two SNPs, MIR211-rs10457441 and AKAP6-rs17522122 were genotyped in 1,570 non-demented older Australians of European ancestry, who were examined up to 4 times over 12 years. Linear mixed effects models were used to examine the association between AKAP6 and MIR2113 with cognitive performance in episodic memory, working memory, vocabulary, perceptual speed and reaction time at baseline and with linear and quadratic rates of change. AKAP6-rs17522122*T was associated with worse baseline performance in episodic memory, working memory, vocabulary and perceptual speed, but it was not associated with cognitive change in any domain. MIR2113-rs10457441*T was associated with accelerated decline in episodic memory. No other associations with baseline cognitive performance or with linear or quadratic rate or cognitive changes was observed for this SNP. These results confirm the previous finding that, AKAP6 is associated with performance across multiple cognitive domains at baseline but not with cognitive decline, while MIR2113 primarily affects the rate at which memory declines over time.

Source connections

Explore related subjects

GeneticsPreprint

Keep this discovery

BibTeXRIS

Shea Andrews, Debjani Das, Kaarin J Anstey, Simon Easteal. 2016-08-19. Association of AKAP6 and MIR2113 with cognitive performance in a population based sample of older adults. https://doi.org/10.1101/070409

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2016

Rapid evolution of primate type 2 immune response factors linked to asthma susceptibility

Host immunity pathways evolve rapidly in response to antagonism by pathogens. Microbial infections can also trigger excessive inflammation that contributes to diverse autoimmune disorders including asthma, lupus, diabetes, and arthritis. Definitive links between immune system evolution and human autoimmune disease remain unclear. Here we provide evidence that several components of the type 2 immune response pathway have been subject to recurrent positive selection in the primate lineage. Notably, rapid evolution of the central immune regulator IL13 corresponds to a polymorphism linked to asthma susceptibility in humans. We also find evidence of accelerated amino acid substitutions as well as repeated gene gain and loss events among eosinophil granule proteins, which act as toxic antimicrobial effectors that promote asthma pathology by damaging airway tissues. These results support the hypothesis that evolutionary conflicts with pathogens promote tradeoffs for increasingly robust immune responses during animal evolution. Our findings are also consistent with the view that natural selection has contributed to the spread of autoimmune disease alleles in humans.

Genetics↗
bioRxiv2016

Single Cell Expression Data Reveal Human Genes that Escape X-Chromosome Inactivation

Sex chromosomes pose an inherent genetic imbalance between genders. In mammals, one of the females X-chromosomes undergoes inactivation (Xi). Indirect measurements estimate that about 20% of Xi genes completely or partially escape inactivation. The identity of these escapee genes and their propensity to escape inactivation remain unsolved. A direct method for identifying escapees was applied by quantifying differential allelic expression from single cells. RNA-Seq fragments were assigned to informative SNPs which were labeled by the appropriate parental haplotype. This method was applied for measuring allelic specific expression from Chromosome-X (ChrX) and an autosomal chromosome as a control. We applied the protocol for measuring biallelic expression from ChrX to 104 primary fibroblasts. Out of 215 genes that were considered, only 13 genes (6%) were associated with biallelic expression. The sensitivity of escapees' identification was increased by combining SNP mapping for parental diploid genomes together with RNA-Seq from clonal single cells (25 lymphoblasts). Using complementary protocols, referred to as strict and relaxed, we confidently identified 25 and 31escapee genes, respectively. When pooled versions of 30 and 100 cells were used, <50% of these genes were revealed. We assessed the generality of our protocols in view of an escapee catalog compiled from indirect methods. The overlap between the escapee catalog and the genes list from this study is statistically significant (P-value of E-07). We conclude that single cells expression data are instrumental for studying X-inactivation with an improved sensitivity. Finally, our results support the emerging notion of the non-deterministic nature of genes that escape X-chromosome inactivation.

Genetics↗
bioRxiv2016

Frequency of mosaicism points towards mutation-prone early cleavage cell divisions.

It has recently become possible to directly estimate the germ-line de novo mutation (dnm) rate by sequencing the whole genome of father-mother-offspring trios, and this has been conducted in human1-5, chimpanzee6, mice7, birds8 and fish9. In these studies dnms are typically defined as variants that are heterozygous in the offspring while being absent in both parents. They are assumed to have occurred in the germ-line of one of the parents and to have been transmitted to the offspring via the sperm cell or oocyte. This definition assumes that detectable mosaicism in the parent in which the mutation occurred is negligible. However, instances of detectable mosaicism or premeiotic clusters are well documented in humans and other organisms, including ruminants10-12. We herein take advantage of cattle pedigrees to show that as much as [~]30% to [~]50% of dnms present in a gamete may occur during the early cleavage cell divisions in males and females, respectively, resulting in frequent detectable mosaicism and a high rate of sharing of multiple dnms between siblings. This should be taken into account to accurately estimate the mutation rate in cattle and other species.

Genetics↗