Meta analysis for diffusion tensor imaging phenotypes

The integrity of the brain’s white matter can serve as an important endophenotype, and several genetic associations have already been established. However, measures derived from DTI, such as fractional anisotropy or tract measures derived from tractography, can vary substantially depending on variables in the imaging acquisition protocols such as the image voxel size, number of directional gradients used, scanner magnetic field strength, and the ratio of the number of directional images to those with no diffusion sensitization. We are therefore forming a DTI working group for phenotype harmonization – to determine several measures computed from DTI images to serve as possible phenotypes to pool together for multi-site genetic analyses. This working group is a methods development group to identify heritable, and reproducible, measures from diffusion images and ways to model or account for inter-site differences in these phenotypes. The group will be dedicated to testing various processing methods, initial phenotypes, and establishing quality control procedures that can be applied practically to large datasets. This will result in an easy-to-implement DTI protocol for all interested ENIGMA sites to use for future meta-analysis in 2013.

Full DTI Working Group Proposal

Publications

1. 2013 Neuroimage: Multi-site genetic analysis of diffusion images and voxelwise heritability analysis: A pilot project of the ENIGMA–DTI working group
2. 2013 Organization of Human Brain Mapping, Seattle WA
   • Poster/Talk 1 – ENIGMA -DTI Overview [pdf] [pptx] *coming soon*
   • Poster/Talk 2 – Using Solar for Mega analyses of additive genetic effects [pdf] [pptx] *coming soon*
3. 2013 International Imaging Genetics Conference, Irvine CA
4. 2012 Organization of Human Brain Mapping, Beijing China

Protocols

Contact