Northern European (> 90%), while the Finnish sample is all of Finnish ancestry. Further details about these samples are given elsewhere (Saccone et al., 2007a). All data collection procedures were approved by institutional review boards at the lead institution, Washington University, the Queensland Institute of Medical Research, and at the University of Helsinki, including the use of appropriate and approved informed consent procedures. Written informed consent was provided by all participants. If the subject was an index case, permission was obtained from them to contact other family members.
