A 3p26-3p25 genetic linkage finding for DSM-IV major depression in heavy smoking families.
Pergadia ML., Glowinski AL., Wray NR., Agrawal A., Saccone SF., Loukola A., Broms U., Korhonen T., Penninx BWJH., Grant JD., Nelson EC., Henders AK., Schrage AJ., Chou Y-L., Keskitalo-Vuokko K., Zhu Q., Gordon SD., Vink JM., de Geus EJC., Macgregor S., Liu JZ., Willemsen G., Medland SE., Boomsma DI., Montgomery GW., Rice JP., Goate AM., Heath AC., Kaprio J., Martin NG., Madden PAF.
OBJECTIVE: The authors tested for genetic linkage of DSM-IV-diagnosed major depressive disorder in families that were ascertained for cigarette smoking. METHOD: Within a study that targeted families characterized by a history of smoking, analyses derived a subset of 91 Australian families with two or more offspring with a history of DSM-IV major depressive disorder (affected sibling pairs, N=187) and 25 Finnish families (affected sibling pairs, N=33). Within this affected sibling pairs design, the authors conducted nonparametric linkage analysis. RESULTS: In the Australian heavy smoking families, the authors found a genome-wide significant multipoint LOD score of 4.14 for major depressive disorder on chromosome 3 at 24.9 cM (3p26-3p25). CONCLUSIONS: Genome-wide significant linkage was detected for major depressive disorder on chromosome 3p in a sample ascertained for smoking. A linkage peak at this location was also observed in an independent study of major depressive disorder.