@article { ISI:000501472300016,
	title = {Educational attainment and allostatic load in later life: Evidence using genetic markers},
	journal = {Preventive Medicine},
	volume = {129},
	year = {2019},
	month = {DEC},
	pages = {105866},
	type = {Article},
	abstract = {Education is strongly correlated with health outcomes in older adulthood. Whether the impact of education expansion improves health remains unclear due to a lack of clarity over the causal relationship. Previous health research within the social sciences has tended to use specific activities of daily living or self-reported health status. This study uses a broader and objective health measure - allostatic load (AL) - to take into consideration the exposures that accumulate throughout the life course. This paper applies a Mendelian Randomization (MR) approach to identify causality in relation to education on health as measured by AL. Using the Health and Retirement Study 2008 (N = 3935), we adopt a polygenic score built from genetic variants associated with years of education. To test whether our analyses violate the exclusion assumption, we further run MR Egger regressions to test for bias from pleiotropy. We also explore the potential pathways between education and AL, including smoking, drinking, marital length, health insurance, etc. Using this genetic instrument, we find a 0.3 unit (19\% of a standard deviation) reduction in AL per year of schooling. The effect is mainly driven by BMI and Hba1c. Smoking and marital stability are two potential pathways that also causally influenced by education. If our main and sensitivity analyses are valid, the results find support that a higher level of education is causally related to better health in older adulthood.},
	keywords = {Allostatic load, Instrumental variable, Mendelian randomization, Polygenic risk score, Years of education},
	issn = {0091-7435},
	doi = {10.1016/j.ypmed.2019.105866},
	author = {Ding, Xuejie and Nicola Barban and Melinda C Mills}
}
@article {10200,
	title = {The relationship between cognitive decline and a genetic predictor of educational attainment.},
	journal = {Soc Sci Med},
	volume = {239},
	year = {2019},
	month = {2019 Sep 13},
	pages = {112549},
	abstract = {<p>Genetic and environmental factors both make substantial contributions to the heterogeneity in individuals{\textquoteright} levels of cognitive ability. Many studies have examined the relationship between educational attainment and cognitive performance and its rate of change. Yet there remains a gap in knowledge regarding whether the effect of genetic predictors on individual differences in cognition becomes more or less prominent over the life course. In this analysis of over 5000 older adults from the Health and Retirement Study (HRS) in the U.S., we measured the change in performance on global cognition, episodic memory, attention \& concentration, and mental status over 14 years. Growth curve models are used to evaluate the association between a polygenic risk score for education (education PGS) and cognitive change. Using the most recent education PGS, we find that individuals with higher scores perform better across all measures of cognition in later life. Education PGS is associated with a faster decline in episodic memory in old age. The relationships are robust even after controlling for phenotypic educational attainment, and are unlikely to be driven by mortality bias. Future research should consider genetic effects when examining non-genetic factors in cognitive decline. Our findings represent a need to understand the mechanisms between genetic endowment of educational attainment and cognitive decline from a biological angle.</p>},
	keywords = {Cognitive decline, Educational attainment, Fluid/crystallised intelligence, Genetic predictor, Growth curve modelling, Polygenic risk score},
	issn = {1873-5347},
	doi = {10.1016/j.socscimed.2019.112549},
	url = {https://www.ncbi.nlm.nih.gov/pubmed/31546143},
	author = {Ding, Xuejie and Nicola Barban and Felix C Tropf and Melinda C Mills}
}
@article {10.3389/fsoc.2019.00074,
	title = {Using Polygenic Scores in Social Science Research: Unraveling Childlessness},
	journal = {Frontiers in Sociology},
	volume = {4},
	year = {2019},
	pages = {74},
	abstract = {Biological, genetic, and socio-demographic factors are all important in explaining reproductive behavior, yet these factors are typically studied in isolation. In this study, we explore an innovative sociogenomic approach, which entails including key socio-demographic (marriage, education, occupation, religion, cohort) and genetic factors related to both behavioral [age at first birth (AFB), number of children ever born (NEB)] and biological fecundity-related outcomes (endometriosis, age at menopause and menarche, polycystic ovary syndrome, azoospermia, testicular dysgenesis syndrome) to explain childlessness. We examine the association of all sets of factors with childlessness as well as the interplay between them. We derive polygenic scores (PGS) from recent genome-wide association studies (GWAS) and apply these in the Health and Retirement Study (N = 10,686) and Wisconsin Longitudinal Study (N = 8,284). Both socio-demographic and genetic factors were associated with childlessness. Whilst socio-demographic factors explain 19{\textendash}46\% in childlessness, the current PGS explains <1\% of the variance, and only PGSs from large GWASs are related to childlessness. Our findings also indicate that genetic and socio-demographic factors are not independent, with PGSs for AFB and NEB related to education and age at marriage. The explained variance by polygenic scores on childlessness is limited since it is largely a behavioral trait, with genetic explanations expected to increase somewhat in the future with better-powered GWASs. As genotyping of individuals in social science surveys becomes more prevalent, the method described in this study can be applied to other outcomes.},
	keywords = {childlessness, polygenic score, social science},
	issn = {2297-7775},
	doi = {10.3389/fsoc.2019.00074},
	url = {https://www.frontiersin.org/article/10.3389/fsoc.2019.00074},
	author = {Verweij, Renske M. and Melinda C Mills and Stulp, Gert and Ilja M Nolte and Nicola Barban and Felix C Tropf and Carrell, Douglas T. and Aston, Kenneth I. and Krina T Zondervan and Rahmioglu, Nilufer and Dalgaard, Marlene and Skaarup, Carina and Hayes, M. Geoffrey and Dunaif, Andrea and Guo, Guang and Snieder, Harold}
}
@article {9912,
	title = {The Sociogenomics of Polygenic Scores of Reproductive Behavior and Their Relationship to Other Fertility Traits},
	journal = {RSF: The Russell Sage Foundation Journal of the Social Sciences},
	volume = {4},
	year = {2018},
	month = {Jan-01-2018},
	pages = {122-136},
	abstract = {Human reproductive behavior until relatively recently has been explained exclusively via individual and social characteristics. This article applies results from a recent Genome-Wide Association Study that combined sixty-two data sources to isolate twelve genetic loci associated with reproductive behavior. We create polygenic scores that allow us to include a summary variable of genetic factors into our statistical models. We use four datasets: the U.S. Health and Retirement Study, Dutch LifeLines, TwinsUK and the Swedish Twin register. First, we provide a brief overview of the dominant explanations of reproductive behavior. Second, we test the predictive power of polygenic scores. Third, we interrogate the robustness of our models using a series of sensitivity analyses to take into account possible confounders due to population stratification and selection.},
	keywords = {Education, Fertility, Genetics, GWAS, PGS},
	issn = {23778253},
	doi = {10.7758/rsf.2018.4.4.07},
	url = {http://www.jstor.org/stable/10.7758/rsf.2018.4.4.07},
	author = {Melinda C Mills and Nicola Barban and Felix C Tropf}
}
@article {8881,
	title = {Genome-wide analysis identifies 12 loci influencing human reproductive behavior.},
	journal = {Nat Genet},
	volume = {48},
	year = {2016},
	month = {2016 Dec},
	pages = {1462-1472},
	abstract = {<p>The genetic architecture of human reproductive behavior-age at first birth (AFB) and number of children ever born (NEB)-has a strong relationship with fitness, human development, infertility and risk of neuropsychiatric disorders. However, very few genetic loci have been identified, and the underlying mechanisms of AFB and NEB are poorly understood. We report a large genome-wide association study of both sexes including 251,151 individuals for AFB and 343,072 individuals for NEB. We identified 12 independent loci that are significantly associated with AFB and/or NEB in a SNP-based genome-wide association study and 4 additional loci associated in a gene-based effort. These loci harbor genes that are likely to have a role, either directly or by affecting non-local gene expression, in human reproduction and infertility, thereby increasing understanding of these complex traits.</p>},
	issn = {1546-1718},
	doi = {10.1038/ng.3698},
	author = {Nicola Barban and Jansen, Rick and de Vlaming, Ronald and Vaez, Ahmad and Mandemakers, Jornt J and Felix C Tropf and Shen, Xia and James F Wilson and Daniel I Chasman and Ilja M Nolte and Tragante, Vinicius and van der Laan, Sander W and Perry, John R B and Kong, Augustine and Ahluwalia, Tarunveer S and Albrecht, Eva and Laura M Yerges-Armstrong and Atzmon, Gil and Auro, Kirsi and Kristin L. Ayers and Bakshi, Andrew and Ben-Avraham, Danny and Klaus Berger and Bergman, Aviv and Bertram, Lars and Bielak, Lawrence F and Bjornsdottir, Gyda and Bonder, Marc Jan and Broer, Linda and Bui, Minh and Barbieri, Caterina and Cavadino, Alana and Chavarro, Jorge E and Turman, Constance and Maria Pina Concas and Cordell, Heather J and Gail Davies and Eibich, Peter and Eriksson, Nicholas and T{\~o}nu Esko and Eriksson, Joel and Falahi, Fahimeh and Felix, Janine F and Mark Alan Fontana and Lude L Franke and Gandin, Ilaria and Gaskins, Audrey J and Gieger, Christian and Gunderson, Erica P and Guo, Xiuqing and Caroline Hayward and He, Chunyan and Edith Hofer and Huang, Hongyan and Joshi, Peter K and Kanoni, Stavroula and Karlsson, Robert and Kiechl, Stefan and Kifley, Annette and Kluttig, Alexander and Kraft, Peter and Lagou, Vasiliki and Lecoeur, Cecile and Lahti, Jari and Li-Gao, Ruifang and Penelope A Lind and Tian Liu and Makalic, Enes and Mamasoula, Crysovalanto and Lindsay K Matteson and Mbarek, Hamdi and McArdle, Patrick F and McMahon, George and Meddens, S Fleur W and Mihailov, Evelin and Michael B Miller and Missmer, Stacey A and Monnereau, Claire and van der Most, Peter J and Myhre, Ronny and Michael A Nalls and Nutile, Teresa and Ioanna Panagiota Kalafati and Porcu, Eleonora and Prokopenko, Inga and Rajan, Kumar B and Rich-Edwards, Janet and Cornelius A Rietveld and Robino, Antonietta and Rose, Lynda M and Rueedi, Rico and Ryan, Kathleen A and Saba, Yasaman and Schmidt, Daniel and Jennifer A Smith and Stolk, Lisette and Streeten, Elizabeth and T{\"o}njes, Anke and Thorleifsson, Gudmar and Ulivi, Sheila and Wedenoja, Juho and J{\"u}rgen Wellmann and Willeit, Peter and Yao, Jie and Yengo, Loic and Jing Hua Zhao and Wei Zhao and Zhernakova, Daria V and Amin, Najaf and Andrews, Howard and Balkau, Beverley and Barzilai, Nir and Bergmann, Sven and Biino, Ginevra and Bisgaard, Hans and B{\o}nnelykke, Klaus and Dorret I Boomsma and Buring, Julie E and Campbell, Harry and Cappellani, Stefania and Ciullo, Marina and Cox, Simon R and Francesco Cucca and Toniolo, Daniela and Davey-Smith, George and Ian J Deary and George Dedoussis and Deloukas, Panos and Cornelia M van Duijn and Eco J. C. de Geus and Johan G Eriksson and Jessica Faul and Cinzia Felicita Sala and Froguel, Philippe and Paolo P. Gasparini and Giorgia G Girotto and Hans-J{\"o}rgen Grabe and Greiser, Karin Halina and Groenen, Patrick J F and de Haan, Hugoline G and Haerting, Johannes and Tamara B Harris and Andrew C Heath and Heikkil{\"a}, Kauko and Hofman, Albert and Homuth, Georg and Holliday, Elizabeth G and John L Hopper and Hypp{\"o}nen, Elina and Jacobsson, Bo and Vincent Jaddoe and Johannesson, Magnus and Jugessur, Astanand and K{\"a}h{\"o}nen, Mika and Kajantie, Eero and Sharon L R Kardia and Keavney, Bernard and Kolcic, Ivana and Koponen, P{\"a}ivikki and Kovacs, Peter and Kronenberg, Florian and Kutalik, Zolt{\'a}n and La Bianca, Martina and Lachance, Genevieve and Iacono, William G and Lai, Sandra and Lehtim{\"a}ki, Terho and David C Liewald and Lindgren, Cecilia M and Yongmei Liu and Luben, Robert and Lucht, Michael and Luoto, Riitta and Magnus, Per and Patrik K E Magnusson and Nicholas G Martin and McGue, Matt and McQuillan, Ruth and Sarah E Medland and Meisinger, Christa and Mellstr{\"o}m, Dan and Andres Metspalu and Traglia, Michela and Lili Milani and Mitchell, Paul and Grant W Montgomery and Dennis O Mook-Kanamori and de Mutsert, Ren{\'e}e and Nohr, Ellen A and Ohlsson, Claes and Olsen, J{\o}rn and Ong, Ken K and Paternoster, Lavinia and Pattie, Alison and Brenda W J H Penninx and Markus Perola and Peyser, Patricia A and Pirastu, Mario and Polasek, Ozren and Power, Chris and Kaprio, Jaakko and Raffel, Leslie J and Katri R{\"a}ikk{\"o}nen and Olli T Raitakari and Ridker, Paul M and Ring, Susan M and Roll, Kathryn and Rudan, Igor and Ruggiero, Daniela and Rujescu, Dan and Veikko Salomaa and Schlessinger, David and Schmidt, Helena and Schmidt, Reinhold and Schupf, Nicole and Johannes H Smit and Sorice, Rossella and Timothy Spector and John M Starr and St{\"o}ckl, Doris and Strauch, Konstantin and Stumvoll, Michael and Swertz, Morris A and Thorsteinsdottir, Unnur and A. Roy Thurik and Nicholas J Timpson and Tung, Joyce Y and Andr{\'e} G Uitterlinden and Vaccargiu, Simona and Viikari, Jorma and Vitart, Veronique and V{\"o}lzke, Henry and Vollenweider, Peter and Vuckovic, Dragana and Waage, Johannes and Wagner, Gert G and Wang, Jie Jin and Wareham, Nicholas J and David R Weir and Gonneke Willemsen and Willeit, Johann and Alan F Wright and Krina T Zondervan and Stefansson, Kari and Krueger, Robert F and Lee, James J and Daniel J. Benjamin and Cesarini, David and Philipp D Koellinger and den Hoed, Marcel and Snieder, Harold and Melinda C Mills}
}
