Anecdotal reports suggest that disease-advocacy groups (DAOs) participate in multiple aspects of clinical research. No systemic analysis of the extent of DAO involvement in clinical genetics research has been conducted to date. We conducted a systematic review of journal articles published in 2004 and 2005 reporting clinical research on 50 genetic diseases to assess the extent to which DAOs financed the studies reported, assisted in subject recruitment, or participated in other aspects of research. Of 513 articles, 350 (68%) included a statement regarding research support. Of these articles, 114 (33%) acknowledged DAO funding. The proportion of articles reporting financial support from a DAO varied greatly by disease. Articles reporting financial support from a DAO often identified at least one additional source of support (73%). Of the articles examined, 19 (4%) acknowledged DAO assistance with subject recruitment and 11 (2%) included an author affiliated with a DAO. DAOs provide financial support for numerous clinical research studies in genetics, often in partnership with government agencies and for-profit corporations. DAOs also participate in other aspects of clinical research, including subject recruitment. Future studies should seek to characterize these research partnerships more fully. © 2010 Wiley-Liss, Inc.