Our sleep timing preference, or chronotype, is a manifestation of our internal biological clock. Variation in chronotype has been linked to sleep disorders, cognitive and physical performance, and chronic disease. Here we perform a genome-wide association study of self-reported chronotype within the UK Biobank cohort (n=100,420). We identify 12 new genetic loci that implicate known components o...

This paper estimates the effects of participating in the National School Lunch Program in the middle of the 20th century on adult health outcomes and educational attainment. I utilize an instrumental variables strategy that exploits a change in the formula used by the federal government to allocate funding to the states. Identification is achieved by the fact that different birth cohorts were e...

This cross-sectional study evaluated knowledge and acceptability of prenatal diagnosis among 500 pregnant women at the University College Hospital, Ibadan. Most participants were aged 25-34 years, self-employed, Muslim, monogamy, secondary school leavers, on income of < naira10,000.00 (US$ 67.00)/month. Attitudinal mean score was dependent on age (p = 0.006), educational attainment (p = 0.001),...

OBJECTIVES Educational opportunities for African-Americans expanded throughout the 20(th) century. Twin pairs are an informative population in which to examine changes in educational attainment because each twin has the same parents and childhood socioeconomic status. We hypothesized that correlation in educational attainment of older twin pairs would be higher compared to younger twin pairs re...