Correlates of intake of folic acid–containing supplements among pregnant women

This study describes the timing and correlates of folic acid supplement intake among pregnant women

Maternal age and risk for trisomy 21 assessed by the origin of chromosome nondisjunction: a report from the Atlanta and National Down Syndrome Projects

Abstract We examined the association between maternal age and chromosome 21 nondisjunction by origin of the meiotic error. We analyzed data from two populationbased, case-control studies: Atlanta Down Syndrome Project (1989Project ( -1999 and National Down Syndrome Project (2001)(2002)(2003)(2004). Cases were live born infants with trisomy 21 and controls were infants without trisomy 21 delivered in the same geographical regions. We enrolled 1,215 of 1,881 eligible case families and 1,375 of 2,293 controls. We report four primary Wndings. First, the signiWcant association between advanced maternal age and chromosome 21 nondisjunction was restricted to meiotic errors in the egg; the association was not observed in sperm or in post-zygotic mitotic errors. Second, advanced maternal age was signiWcantly associated with both meiosis I (MI) and meiosis II (MII). For example, compared to mothers of controls, mothers of infants with trisomy 21 due to MI nondisjunction were 8.5 times more likely to bȩ 40 years old than 20-24 years old at the birth of the index case (95% CI = 5.6-12.9). Where nondisjunction occurred in MII, mothers were 15.1 times more likely to be ¸40 years (95% CI = 8.4-27.3). Third, the ratio of MI to MII errors diVered by maternal age. The ratio was lower among women <19 years of age and those ¸40 years (2.1, 2.3, respectively) and higher in the middle age group (3.6). Lastly, we found no eVect of grand-maternal age on the risk for maternal nondisjunction. This study emphasizes the complex association between advanced maternal age and nondisjunction of chromosome 21 during oogenesis

Wordplay in Shakespeare's Hamlet and the Accusation of Derrida's “Logical Phallusies”

That “Derrida's writing borders on being unreadable” has been maintained by several academics, journalists and students. This essay considers this reaction to Jacques Derrida's writing in relation to a broader history of wordplay and puns. Using Shakespeare's Hamlet as a starting point followed by the infamous letter to The Times that accused Derrida of “logical phallusies”, it argues that if Derrida's writing does border on being unreadable, then, this is the condition of all writing. The essay suggests that rather than suppressing the spectres of Derrida in Shakespeare studies, we should welcome back the aspects of his work that help us to “read and write in the space or heritage of Shakespeare”

The National Down Syndrome Project: Design and Implementation

OBJECTIVE: The National Down Syndrome Project (NDSP), based at Emory University in Atlanta, Georgia, represents a multi-site, population-based, case-control study with two major aims: (1) to identify molecular and epidemiological factors contributing to chromosome nondisjunction and the consequent packaging of an extra chromosome into an egg or sperm, and (2) to identify risk factors for Down syndrome-associated birth defects. METHODS: The six national sites represent approximately 11% of U.S. births. Cases were newborns with Down syndrome (trisomy 21), and controls were infants without major birth defects randomly selected from the same birth populations. Biological samples were collected from case infants and their parents, and genetic markers were typed to determine the parental origin of chromosome 21 nondisjunction. Each site interviewed parents of case and control infants addressing pregnancy, medical and family history, occupation, and exposures. Sites collected medical information on case infants. RESULTS: The NDSP enrolled 907 infants as cases and 977 infants as controls (participation rates: 60.7% for cases; 56.9% for controls). Participation rates varied widely by site as did important demographic factors such as maternal age, race, and education. Nondisjunction during oogenesis accounted for 93.2% of the cases. Errors in spermatogenesis were found in 4.1%, and 2.7% were post-zygotic errors. CONCLUSIONS: This exceptional compilation of questionnaire, clinical, and molecular data makes the NDSP a unique resource for ongoing studies of the etiology and phenotypic consequences of trisomy 21. The combined approach increases study power by defining subgroups of cases by the origin of nondisjunction. This report describes the design and successful implementation of the NDSP