An interaction between the catechol O-methyltransferase and serotonin transporter promoter region polymorphisms contributes to tridimensional personality questionnaire persistence scores in normal subjects.
Persistence (RD2) is a subscale of the reward dependence trait, one of the three major personality factors assessed by the Tridimensional Personality Questionnaire (TPQ). Subjects with high RD2 scores are characterized as industrious, hard-working, ambitious, perfectionistic. TPQ scores were examined in 577 normal subjects inventoried for two common genetic polymorphisms, the catechol O-methyltransferase (COMT) valine to methionine (val to met) amino acid substitution that determines high and low enzyme activity, and the serotonin transporter promoter region 44 bp deletion (5-HTTLPR) linked in some studies to harm avoidance or neuroticism. When TPQ RD2 scores are grouped by COMT and 5-HTTLPR polymorphisms and analyzed by two-way ANOVA, significant main effects for COMT (F = 2. 98, p = 0.05) and 5-HTTLPR (F = 4.27, p = 0.04) and a significant interaction COMT x 5-HTTLPR (F = 6.18, p = 0.002) are observed. In the presence of COMT homozygosity (val/val or met/met genotypes), the presence of the short 5-HTTLPR allele raises RD2 scores. The effect of these two polymorphisms on RD2 was also examined using a within-families design. Siblings in our data set who shared identical genotypes had significantly correlated RD2 scores (intraclass coefficient = 0.34, F = 2.03, p = 0.002, n = 67), whereas sibs with dissimilar genotypes in at least one polymorphism showed no significant correlation for RD2 scores (intraclass coefficient = 0.105, F = 1.23, p = 0.16, n = 92).
Benjamin
J
J
Faculty of Health Sciences, Ben Gurion University of the Negev, Beersheva, Israel.
Osher
Y
Y
Lichtenberg
P
P
Bachner-Melman
R
R
Gritsenko
I
I
Kotler
M
M
Belmaker
R H
RH
Valsky
V
V
Drendel
M
M
Ebstein
R P
RP
D000293:Adolescent; D000328:Adult; D000483:Alleles; D000704:Analysis of Variance; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D007557:Israel; D008297:Male; D010551:Personality / Q000235:genetics* / Q000502:physiology; D010555:Personality Inventory; D011110:Polymorphism, Genetic / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D012016:Reference Values; D012201:Reward; D012494:Sampling Studies; D012701:Serotonin / Q000235:genetics*
D012701:Serotonin; D002394:Catechol O-Methyltransferase