Gene-environment interaction of child temperament.
OBJECTIVE
The aims of this study were to review studies on the molecular genetics of child temperament and prospectively analyze infant temperament as a function of the interaction between infant and mother: 5-HTT, DRD4, and MAO-A functional polymorphisms and the mother's emotional state.


METHODS
A prospective study of 317 newborns and their mothers was performed. Infant temperament and the mother's anxiety and confidence in caregiving were evaluated at 8 and 32 weeks after childbirth using the Mother and Baby Scale. The mother's emotional state was evaluated using the Edinburgh Postpartum Depression Scale and the State-Trait Anxiety Inventory. These variables were correlated with 5-HTTLPR and Stin2 variants in the 5-HTT gene and the DRD4 variable number tandem repeats Exon 3 and MAO-A variable number tandem repeats genotypes of both the infants and their mothers.


RESULTS
The irritability scores of infants with the 5-HTTLPR s allele showed a linear relationship with their mothers' anxiety of caregiving at 8 (p = .011) and 32 weeks (p = .001), whereas the irritability of infants carrying the HTTLPR ll genotype was independent of their mothers' anxiety.


CONCLUSIONS
The review of the literature in this field and the results of this study support that the 5-HTTLPR polymorphism moderates the influence of the mother's anxiety on infant irritability.
Ivorra
Jose Luis
JL
Department of Genetics, Faculty of Medicine, Valencia University, Spain.
Sanjuan
Julio
J
Jover
Manuel
M
Carot
Jose Miguel
JM
Frutos
Rosa de
Rd
Molto
Maria Dolores
MD
D000328:Adult; D001007:Anxiety / Q000235:genetics* / Q000523:psychology; D004777:Environment; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D018730:Infant Behavior / Q000523:psychology*; D007231:Infant, Newborn; D008297:Male; D008425:Maternal Behavior / Q000523:psychology; D008995:Monoamine Oxidase / Q000235:genetics; D009034:Mother-Child Relations; D009035:Mothers / Q000523:psychology*; D011110:Polymorphism, Genetic; D049590:Postpartum Period; D011247:Pregnancy; D011446:Prospective Studies; D050638:Receptors, Dopamine D4 / Q000235:genetics; D012307:Risk Factors; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D013694:Temperament; D013997:Time Factors
C493599:DRD4 protein, human; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D050638:Receptors, Dopamine D4; D008995:Monoamine Oxidase