@article {6566,
	title = {Novel loci associated with usual sleep duration: the CHARGE Consortium Genome-Wide Association Study.},
	journal = {Mol Psychiatry},
	volume = {20},
	year = {2015},
	month = {2015 Oct},
	pages = {1232-9},
	abstract = {<p>Usual sleep duration is a heritable trait correlated with psychiatric morbidity, cardiometabolic disease and mortality, although little is known about the genetic variants influencing this trait. A genome-wide association study (GWAS) of usual sleep duration was conducted using 18 population-based cohorts totaling 47 180 individuals of European ancestry. Genome-wide significant association was identified at two loci. The strongest is located on chromosome 2, in an intergenic region 35- to 80-kb upstream from the thyroid-specific transcription factor PAX8 (lowest P=1.1 {\texttimes} 10(-9)). This finding was replicated in an African-American sample of 4771 individuals (lowest P=9.3 {\texttimes} 10(-4)). The strongest combined association was at rs1823125 (P=1.5 {\texttimes} 10(-10), minor allele frequency 0.26 in the discovery sample, 0.12 in the replication sample), with each copy of the minor allele associated with a sleep duration 3.1 min longer per night. The alleles associated with longer sleep duration were associated in previous GWAS with a more favorable metabolic profile and a lower risk of attention deficit hyperactivity disorder. Understanding the mechanisms underlying these associations may help elucidate biological mechanisms influencing sleep duration and its association with psychiatric, metabolic and cardiovascular disease. </p>},
	keywords = {Adult, African Americans, Aged, Dyssomnias, European Continental Ancestry Group, Female, Genetic Association Studies, Genome-Wide Association Study, Humans, Male, Middle Aged, Polymorphism, Single Nucleotide, Self Report, Sleep},
	issn = {1476-5578},
	doi = {10.1038/mp.2014.133},
	author = {Gottlieb, D J and Hek, K and Chen, T-H and Watson, N F and Eiriksdottir, G and Byrne, E M and Cornelis, M and Warby, S C and Bandinelli, S and Cherkas, L and Evans, D S and Grabe, H J and Lahti, J and Li, M and Lehtim{\"a}ki, T and Lumley, T and Marciante, K D and P{\'e}russe, L and Psaty, B M and Robbins, J and Tranah, G J and Vink, J M and Wilk, J B and Stafford, J M and Bellis, C and Biffar, R and Bouchard, C and Cade, B and Curhan, G C and Eriksson, J G and Ewert, R and Ferrucci, L and F{\"u}l{\"o}p, T and Gehrman, P R and Goodloe, R and Harris, T B and Heath, A C and Hernandez, D and Hofman, A and Hottenga, J-J and Hunter, D J and Jensen, M K and Johnson, A D and K{\"a}h{\"o}nen, M and Kao, L and Kraft, P and Larkin, E K and Lauderdale, D S and Luik, A I and Medici, M and Montgomery, G W and Palotie, A and Patel, S R and Pistis, G and Porcu, E and Quaye, L and Raitakari, O and Redline, S and Rimm, E B and Rotter, J I and Smith, A V and Spector, T D and Teumer, A and Uitterlinden, A G and Vohl, M-C and Widen, E and Willemsen, G and Young, T and Zhang, X and Liu, Y and Blangero, J and Boomsma, D I and Gudnason, V and Hu, F and Mangino, M and Martin, N G and O{\textquoteright}Connor, G T and Stone, K L and Tanaka, T and Viikari, J and Gharib, S A and Punjabi, N M and R{\"a}ikk{\"o}nen, K and V{\"o}lzke, H and Mignot, E and Tiemeier, H}
}
@article {7564,
	title = {Short telomere length is associated with impaired cognitive performance in European ancestry cohorts.},
	journal = {Transl Psychiatry},
	volume = {7},
	year = {2017},
	month = {2017 04 18},
	pages = {e1100},
	abstract = {<p>The association between telomere length (TL) dynamics on cognitive performance over the life-course is not well understood. This study meta-analyses observational and causal associations between TL and six cognitive traits, with stratifications on APOE genotype, in a Mendelian Randomization (MR) framework. Twelve European cohorts (N=17 052; mean age=59.2{\textpm}8.8 years) provided results for associations between qPCR-measured TL (T/S-ratio scale) and general cognitive function, mini-mental state exam (MMSE), processing speed by digit symbol substitution test (DSST), visuospatial functioning, memory and executive functioning (STROOP). In addition, a genetic risk score (GRS) for TL including seven known genetic variants for TL was calculated, and used in associations with cognitive traits as outcomes in all cohorts. Observational analyses showed that longer telomeres were associated with better scores on DSST (β=0.051 per s.d.-increase of TL; 95\% confidence interval (CI): 0.024, 0.077; P=0.0002), and MMSE (β=0.025; 95\% CI: 0.002, 0.047; P=0.03), and faster STROOP (β=-0.053; 95\% CI: -0.087, -0.018; P=0.003). Effects for DSST were stronger in APOE ɛ4 non-carriers (β=0.081; 95\% CI: 0.045, 0.117; P=1.0 {\texttimes} 10-5), whereas carriers performed better in STROOP (β=-0.074; 95\% CI: -0.140, -0.009; P=0.03). Causal associations were found for STROOP only (β=-0.598 per s.d.-increase of TL; 95\% CI: -1.125, -0.072; P=0.026), with a larger effect in ɛ4-carriers (β=-0.699; 95\% CI: -1.330, -0.069; P=0.03). Two-sample replication analyses using CHARGE summary statistics showed causal effects between TL and general cognitive function and DSST, but not with STROOP. In conclusion, we suggest causal effects from longer TL on better cognitive performance, where APOE ɛ4-carriers might be at differential risk.</p>},
	keywords = {Adult, Aged, Apolipoprotein E4, Cognitive Dysfunction, Cohort Studies, European Continental Ancestry Group, Female, Genetic Carrier Screening, Genotype, Humans, Male, Mendelian Randomization Analysis, Middle Aged, Neuropsychological Tests, Psychometrics, Statistics as Topic, Telomere},
	issn = {2158-3188},
	doi = {10.1038/tp.2017.73},
	author = {H{\"a}gg, S and Zhan, Y and Karlsson, R and Gerritsen, L and Ploner, A and van der Lee, S J and Broer, L and Deelen, J and Marioni, R E and Wong, A and Lundquist, A and Zhu, G and Hansell, N K and Sillanp{\"a}{\"a}, E and Fedko, I O and Amin, N A and Beekman, M and de Craen, A J M and Degerman, S and Harris, S E and Kan, K-J and Martin-Ruiz, C M and Montgomery, G W and Adolfsson, A N and Reynolds, C A and Samani, N J and Suchiman, H E D and Viljanen, A and von Zglinicki, T and Wright, M J and Hottenga, J-J and Boomsma, D I and Rantanen, T and Kaprio, J A and Nyholt, D R and Martin, N G and Nyberg, L and Adolfsson, R and Kuh, D and Starr, J M and Deary, I J and Slagboom, P E and van Duijn, C M and Codd, V and Pedersen, N L}
}
