remain in the line-up (Galaburda et al., 2006; Paracchini, Scerri & Monaco, 2007). Turning to association studies, they have focused on ‘candidate’ genes using DNA markers in coding regions, especially ‘functional’ DNA markers that code for amino acid sequence differences. However, progress has been slow in identifying replicable associations. Moreover, when associations are found with DNA markers in ‘intergenic’ regions, the associations have been dismissed as invalid for that reason.
