Melanocortin 4 receptor sequence variations are seldom a cause of human obesity: the Swedish obese subjects, the HERITAGE family study, and a Memphis cohort. - Jacobson,P.; Ukkola,O.; Rankinen,T.; Snyder,E.E.; Leon,A.S.; Rao,D.C.; Skinner,J.S.; Wilmore,J.H.; Lonn,L.; Cowan,G.S.; Sjostrom,L.; Bouchard,C. (J Clin Endocrinol Metab, 2002)