Genetic associations with quantitative phenotypes (e.g. those obtained through MR imaging) can be investigated in sufficiently large datasets. These studies have the advantage of defining a trait in a precise manner, thus ameliorating the challenge posed by clinical heterogeneity observed in most complex diseases. We have conducted associations with total brain glutamate (Baranzini et al; Brain, 2010) and white matter lesion distribution (Gourraud et al. Brain; 2013). Methods: Statistical genetics, bioinformatics.
|Lesion distribution maps. Lesions were computationally reconstructed in 2 patients from MRI data acquired at 1mm3 resolution. Despite both patients having similar lesion load, the one illustrated in panel A shows fewer, larger lesions. The patient depicted on panel B has more, but smaller lesions.|