Article

Merging and emerging cohorts: necessary but not sufficient.

National Human Genome Research Institute, National Institutes of Health, 31 Center Drive, Bethesda, Maryland 20892-2152, USA.
Nature (Impact Factor: 42.35). 02/2007; 445(7125):259. DOI: 10.1038/445259a
Source: PubMed
0 Followers
 · 
59 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: During the past 15 years, an impressive amount of genetic information has become available in the research field of psychiatry, particularly as it relates to attention-deficit/hyperactivity disorder (ADHD). However, the classical clinical approach to ADHD has minimally affected and not significantly been improved by this genetic revolution. It is difficult to predict how long it will take for genetic findings to alter the way clinicians treat patients with ADHD. New medications or treatment protocols may take years to become routine clinical practice. However, when taken together, recent successes in genomics, pharmacogenomics, and genetic epidemiology have the potential (1) to prevent comorbid consequences of ADHD, (2) to individualize therapies for patients with ADHD, and (3) to define new epidemiological policies to aid with the impact of ADHD on society. Here, we present an overview of how genetic research may affect and improve the quality of life of patients with ADHD: as an example, we use the discovery of LPHN3, a new gene in which variants have recently been shown to be associated with ADHD.
    ADHD Attention Deficit and Hyperactivity Disorders 11/2010; 2(3):139-47. DOI:10.1007/s12402-010-0030-2
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Advances in high-throughput genotyping and a flood of data on human genetic variation from the Human Genome and HapMap projects have made genome-wide association studies technically feasible. However, researchers designing such studies face a number of challenges, including how to avoid subtle systematic biases and how to achieve sufficient statistical power to distinguish modest association signals from chance associations. In many situations, it remains prohibitively expensive to genotype all the desired samples using a genome-wide genotyping array, so multistage designs are an attractive cost-saving measure. Here, we review some of the basic design principles for genetic association studies, discuss the properties of fixed genome-wide and custom genotyping arrays as they relate to study design, and present a theoretical framework and practical tools for power calculations. We close with a discussion of the limitations of multistage designs.
    Advances in genetics 02/2008; 60:465-504. DOI:10.1016/S0065-2660(07)00417-8 · 5.41 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Pyrolysis kinetics of a gingko nut shell in a thermo gravimetric analyzer (TGA) and the steam gasification and combustion kinetics of chars from gingko nut shell in a thermobalance reactor have been determined. The effects of the reaction temperature (350°C–950°C) and steam partial pressure (0.4–0.8 atm.) on the gasification kinetics and that of oxygen partial pressure (0.4–0.8 atm.) on the combustion kinetics have been determined in a thermobalance reactor. The activation energy and the pre-exponential factor were determined from the Arrhenius plot based on the shrinking core model. In the steam gasification reaction, the activation energy and the pre-exponential factor are found to be 40.8 kJ mol−1 at 1.7 s−1 atm.−1, respectively. The reaction order is found to be 0.32 with respect to water partial pressure at 750°C. In the combustion reaction, the activation energies and pre-exponential factors are found to be 92.8 kJmol−1 at 136.8 s−1 and 9.2 kJmol−1 at 0.012 s−1 atm−1 in the reaction control and the pore-diffusion control regimes, respectively.