Dopamine D4 receptor (DRD4) polymorphism and adaptability trait during infancy: a longitudinal study in 1- to 5-month-old neonates.
We have examined the relationship between the common dopamine D4 receptor (DRD4) exon III repeat polymorphism and infants' behavior measured with the Italian version of the Early and Revised Infancy Temperament Questionnaires (EITQ/RITQ) in 122 Italian neonates at 1 and 5 months of life, when the genetic contribution to the behavior can be more clearly assessed. Two-way (genotype x age) analysis of variance revealed a significant correlation with the temperamental subscale of adaptability [F(1, 120) = 5.26, P < 0.02]. At 1 month of life (early assessment), infants with long (L) DRD4 alleles presented significantly low scores (L 2.61 +/- 0.073; S 2.84 + 0.79; Newman-Keuls P = 0.03) in comparison with the high scores of infants with short (S) alleles (L 2.4 +/- 0.059; S 2.25 +/- 0.57). These differences were not detected at 5 months of life (late assessment), denoting a strong environmental effect at this age on the genetic background. These results confirm and extend the genetic influence of the DRD4 gene in human temperament at birth.
De Luca
A
A
Dipartimento di Biopatologia e Diagnostica per Immagini, Sezione di Genetica, Università di Roma Tor Vergata, Via di Tor Vergata 135, 00133 Rome, Italy.
Rizzardi
M
M
Torrente
I
I
Alessandroni
R
R
Salvioli
G P
GP
Filograsso
N
N
Dallapiccola
B
B
Novelli
G
G
D000223:Adaptation, Psychological; D000704:Analysis of Variance; D005091:Exons; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D007558:Italy; D008137:Longitudinal Studies; D008297:Male; D011110:Polymorphism, Genetic; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D050638:Receptors, Dopamine D4; D011795:Surveys and Questionnaires; D013694:Temperament; D044465:White People
C493599:DRD4 protein, human; D017448:Receptors, Dopamine D2; D050638:Receptors, Dopamine D4