Prenatal maternal depression and a multilocus genetic profile of two susceptibility genes implicated in the stress response were examined in an interaction model predicting negative emotionality (NE) in the first 3 years. In 179 mother-infant dyads from the Maternal Adversity, Vulnerability and Neurodevelopment cohort, prenatal depression (CES-D) was assessed at 24 to 36 weeks. The multilocus genetic profile score consisted of the number of susceptibility alleles from 5-HTTLPR (No L A (S/S, S/L G or L G /L G ) vs. any L A ) and Dopamine Receptor D4 (6-8R vs. 2-5R). NE was extracted from the IBQ-R at 3 and 6 months and the ECBQ at 18 and 36 months. Mixed and confirmatory regression analyses indicated that prenatal depression and the multilocus genetic profile interacted to predict NE from 3 to 36 months. Results were characterised by a differential susceptibility model at 3 and 6 months and by a diathesis stress model at 36 months. Negative emotionality (NE) is derived from the temperamental dimensions of sadness, distress towards limitations, fear and excessive reactions to minor changes, and reflects a generally stable tendency to show increased emotional reactivity towards negative situations (Gartstein & Rothbart, 2003;Lemery, Goldsmith, Klinnert, & Mrazek, 1999). NE is associated with the development of later problematic behaviour and psychopathology (Eisenberg et al., 2009;Fox, Henderson, Rubin, Calkins, & Schmidt, 2001;Hyde, Mezulis, & Abramson, 2008). For example, fearful temperament is associated with childhood anxiety disorders (Degnan, Alma, & Fox, 2010;Goldsmith & Lemery, 2000), while NE is associated with depression (Phillips, Lonigan, & Driscoll, 2002) and maladjustment (Eisenberg et al., 2009). Understanding early influences of NE on socio-emotional development (Davis, Glynn, Schetter, Hobel, Chicz-demet, & Sandman, 2007;Davis, Snidman, Glynn, Dunkel Schetter, & Sandman, 2004;Hayden et al., 2010;Hayden et al., 2007) could inform efforts at prevention and early intervention. Recent contradictory findings about the role of genetic and prenatal adversity (Braithwaite et al., 2013;, suggest the need for replication (Duncan, 2013) and modeling of genetic risk with multiple genes (Plomin, 2013). Accordingly, we present the findings from a study of the development of NE from 3 to 36 months of age from the interaction of prenatal maternal depression and a multilocus genetic profile. The Role of Prenatal Maternal StressPrenatal maternal stress, measured in diverse ways is associated with NE (Glover, 2011;O'Connor, Heron, & Glover, 2002a). For example, higher prenatal maternal cortisol is associated with fussier behaviour, more negative facial expressions, crying, as well as higher NE at 7 weeks of age (de Weerth, Hees, & Buitelaar, 2003). Symptoms of prenatal maternal anxiety and depression, loosely associated with the stress response predict behavioural reactivity at 4 months of age (Davis et al., 2004) and behavioural/emotional problems at 4 years of age (O'Connor, et al., 2002a). While most studi...

These results do not suggest a major role of the short variant of 5-HTTLPR in susceptibility to SAD, but provide modest evidence for an effect on seasonality.