Because culturally-mediated behaviors can significantly influence the distribution of phenotype, they are best understood through collaboration between local investigators who have the cultural and clinical experience to collect valid data and researchers with phenotype-specific and analytical expertise. The collection of samples among non-urban families enriched for AD dependence would not have been possible without this fruitful collaboration, and expands our understanding of the impact of genetic variation in China beyond the major urban centers where most previous genetic samples have been collected.
