title: Identifying the interaction of maternal sensitivity and two serotonin-related gene polymorphisms on infant self-regulation.
abstract: During infancy, orienting and gaze aversion serve as major self-regulatory mechanisms and play an important role in the development of deliberate self-regulation and control. The present study examined the interaction of intrinsic factors (MAOA-uVNTR and 5-HTTLPR gene polymorphisms) and extrinsic factors (maternal sensitivity) on early infant self-regulatory behavior. We assessed 5-HTTLPR (ss+sl versus ll) and MAOA-uVNTR (3 and 4 among boys, and 3/3, 3/4, and 4/4 among girls) polymorphisms, determined maternal sensitivity during mother-child free play, and coded infant self-regulatory behavior (i.e., orienting shifts in a temperament test) in 281 six-month-old infants. We found that infants who experienced a lower level of maternal sensitivity and had the short allele of 5-HTTLPR variants and the 3/3 MAOA-uVNTR polymorphism displayed lower self-regulation capacity than did those infants with a higher level of maternal sensitivity. This finding suggested a modulatory role of maternal sensitivity. Moreover, these findings are consistent with the genetic vulnerability hypothesis, which states that beneficial environmental factors serve as a buffer against harmful genetic predispositions during child development.
authors.affiliation: Ludong University, China.
authors.forename: Minghao
authors.initials: M
authors.lastname: Zhang
authors.affiliation: University of Pennsylvania, United States.
authors.forename: Xinyin
authors.initials: X
authors.lastname: Chen
authors.affiliation: Southeast University, China.
authors.forename: Huihua
authors.initials: H
authors.lastname: Deng
authors.affiliation: Pecking University, China. Electronic address: zhlu@seu.edu.cn.
authors.forename: Zuhong
authors.initials: Z
authors.lastname: Lu
mesh_terms: D004247:DNA / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D007223:Infant; D018730:Infant Behavior / Q000502:physiology*; D008297:Male; D018598:Minisatellite Repeats / Q000235:genetics; D008995:Monoamine Oxidase / Q000235:genetics; D009034:Mother-Child Relations / Q000523:psychology*; D009035:Mothers / Q000523:psychology*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012701:Serotonin / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics; D012727:Sex Characteristics; D012927:Social Control, Informal
chemical_list: C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin; D004247:DNA; D008995:Monoamine Oxidase
keywords: 5-HTTLPR polymorphism; Gene interaction; Gene–environment interaction; MAOA-uVNTR polymorphism; Maternal sensitivity