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Epigenetic modifications of the membrane bound catechol-O-methyltransferase (MB-COMT) gene may affect the enzymatic degradation of dopamine, and consequently, human behavior. This study investigated the association between membrane bound catechol-O-methyltransferase DNA methylation (DNAm) differences in 92 monozygotic (MZ) twins with phenotypic manifestations of cognitive, behavioral, and personality indicators associated with reward-related behaviors and lack of control. We used pyrosequencing to determine DNAm of the regulatory region of membrane bound catechol-O-methyltransferase in saliva DNA. Results of intrapair differences in the percentage of membrane bound catechol-O-methyltransferase DNAm at each of five CpG sites show that there are associations between phenotypic indicators of lack of control and membrane bound catechol-O-methyltransferase DNAm differences on CpG1, CpG2 and CpG4, suggesting the common epigenetic patterns for personality traits, cognitive functions, and risk behaviors.

Aggressive and impulsive behaviors have shown sufficient genetic influences and high co-occurrence, thus the question is whether dispositions for these behaviors share unique genetic or environmental contributions. The aim of this research was to explore etiology of phenotypic relationships between aggressiveness and impulsiveness. More precisely, we tested which component of aggressiveness (affective, behavioral, or cognitive) shared the most underlying genetic and environmental influences with impulsiveness. There were applied Serbian adaptation of the Buss-Perry Aggression Questionnaire as a measure of three aggressiveness components, and Behavioral Activation System scale from the Revised Sensitivity Theory Questionnaire as a measure of impulsiveness, on a sample of 208 adult twin pairs (132 pairs were monozygotic). Results of a multivariate biometric method showed that the aggressiveness and impulsiveness could be explained by the common additive genetic (6% of impulsiveness and 16- 31% of aggressiveness components), and common non-shared environmental contributions (1% of impulsiveness and 11-47% of aggressiveness components), but those contributions were rather small. An affective component of aggressiveness (anger) showed the most genetic similarity with impulsiveness, indicating that the lack of anger and behavior regulation shared partially the same genetic basis. However, aggressiveness and impulsiveness contained a larger proportion of the specific genetic and environmental effects, which confirmed a distinction between these phenomena.

Inteligencija i školsko postignuće, kao tesno vezani, ispitivani su zajedno od najranijih empirijskih istraživanja ovih konstrukata. Međutim, tek rezultati bihejvioralno-genetičkih studija pružaju potpunu sliku o faktorima koji utiču na inteligenciju i školski uspeh, specifikujući etiologiju njihovog odnosa. Osnovni cilj ovog istraživanja usmeren je na procenu genetskih i sredinskih faktora koji utiču na kovariranje među merom opšte intelektualne sposobnosti i osnovnoškolskog i srednjoškolskog uspeha. Istraživanje je obuhvatilo 340 parova blizanaca oba pola, od toga 168 monozigotnih i 172 dizigotna blizanca, u starosnoj dobi 18–44 godine. Udeo pojedinih izvora kovariranja između ispitivanih fenotipa testiran je multivarijantnim biometrijskim metodom. Uvid u fenotipske korelacije opšte intelektualne sposobnosti, uspeha u osnovnoj školi i uspeha u srednjoj, ukazuje da je reč o konstruktima koji međusobno umereno koreliraju (.33–.53). Opšti/zajednički genetski uticaj objašnjava najveći deo kovarijanse školskog uspeha (kako u osnovnoj, tako i u srednjoj školi) i opšte intelektualne sposobnosti, što govori u prilog pretpostavci da isti set gena određuje etiologiju individualnih razlika na ispitivanim varijablama. Objašnjenju korelacije između uspeha u osnovnoj i uspeha u srednjoj školi umereno doprinose i mere opšte/zajedničke deljene sredine. Pored nedeljenih sredinskih uticaja, ono što razlikuje ispitivane konstrukte jesu uticaji specifičnih genetskih faktora, koji su jedinstveni za svaki konstrukt.

U radu su prikazane tri studije čiji je cilj bio provera mernih svojstava simulacije Cattellovog upitnika 16PF, razvijene u okviru projekta 'International Personality Item Pool'. Rezultati prve studije, u kojoj je ovim upitnikom ispitano 447 ispitanika, ukazuju na prihvatljive koeficijente pouzdanosti većine skala, kao i na postojanje pet opštih faktora koji u izvesnoj meri odgovaraju Cattellovim pretpostavkama. Glavne razlike u odnosu na pretpostavljenu strukturu uočavaju se u oblasti interpersonalnih dimenzija. U okviru druge studije istraživane su korelacije rezultata na skalama IPIP 16PF sa opštim uspehom u školi i uspehom u nekoliko školskih predmeta. Ispitivanjem su obuhvaćena 222 učenika završnog razreda gimnazije. Dobijene korelacije su generalno niske, a sa uspehom u najvećem broju školskih predmeta koreliraju skale Dužnost (G), Osetljivost (I), Inteligencija (B) i Kompleksnost (Q1). Rezultati treće studije, u kojoj je ispitano 115 učenika završnog razreda gimnazije, pokazuju da se na osnovu rezultata na skalama IPIP 16PF mogu predvideti raspoloženja u neutralnoj i predispitnoj situaciji, procenjena upitnikom STCI-S. Prediktivna moć skala je veća u slučaju neutralne, nego u slučaju predispitne situacije. Značajni prediktori raspoloženja u neutralnoj situaciji su skale Emocionalna stabilnost (C), Anksioznost (O), Emocionalnost (Q4) i Kompleksnost (Q1). U predispitnoj situaciji ove skale gube sposobnost predikcije, a kao značajni prediktori se pojavljuju Inteligencija (B), Introverzija (Q2) i Asertivnost (E). Rezultati sve tri studije idu u prilog korisnosti primene upitnika IPIP 16PF u psihološkim istraživanjima, ali ukazuju i na izvesne njegove nedostatke.

BackgroundBreech presentation (BP) results from at random filling of the intrauterine cavity, with an equal probability for a BP or cephalic presentation (CP). Each fetus in BP has its “pair” in CP randomly assumed CP. Direct comparison of BP and CP makes bias to less expressed differences between these two groups. It is therefore necessary to subtract the number of fetuses/newborns from the CP set that are identical to the number of fetuses/newborns in the BP set, with identical characteristics, and add this group to the BP set before comparing them to the rest of the CP fetuses/newborns in the matching process.MethodsThe procedure encompasses nine variables in pregnancies with a congenitally malformed uterus (CMU) identified at the Department of Obstetrics (1985–2014): gestational age, birth mass, birth length, head circumference, shoulders circumference, umbilical length, placental weight, newborn mass/newborn length ratio, and newborn mass/placental mass ratio. Firstly, the probability of BP was determined and its relation to gestational age, physical characteristics, and previous presentations. Then direct comparison as well as case–control matching of the CP and BP were performed. Case–control matching was based on either a single specific variable (M1) or all combined variables (M2).Findings462 deliveries were identified with CMU. In 81 cases of multiparity, a fetal presentation was found to be an independent event regardless of the previous presentation, gestational age, and newborn physical characteristics. In four types of CMU with 337 deliveries (Bicornuate, Didelphys, Unicornuate, Arcuate), 9 variables with 36 instances of comparison were observed. M1 in 10 instances and M2 in 6 instances showed a statistically significant lower value of breech/random presentation compared with CP. CP have lower value in 2 instances in M1 and 1 in M2. Statistically significant differences were absent without the matching process.InterpretationsThe study confirms the maximum probability for the BP is 50%. The case–control matching procedure shows that it is able to detect the difference between the breech/random presentation and CP, while the classic method of direct comparison was unable to detect any differences. The outcome of the breech/random presentation in CMU should be evaluated with the described case–control matching procedure.