BACKGROUND/AIMS:The application of intranasal oxytocin enhances facial emotion recognition in normal subjects and in subjects with autism spectrum disorders (ASD). In addition, various features of social cognition have been associated with variants of the oxytocin receptor gene (OXTR). Therefore, we tested for associations between mind-reading, a measure for social recognition and OXTR polymorphisms.METHODS:76 healthy adolescents and young adults were tested for associations between OXTR rs53576, rs2254298, rs2228485 and mind-reading using the "Reading the Mind in the Eyes Test" (RMET).RESULTS:After Bonferroni correction for multiple comparisons, rs2228485 was associated with the number of incorrect answers when subjects evaluated male faces (P =0.000639). There were also associations between OXTR rs53576, rs2254298 and rs2228485 and other RMET dimensions according to P <0.05 (uncorrected).CONCLUSION:This study adds further evidence to the hypothesis that genetic variations in the OXTR modulate mind-reading and social behaviour.
Associations of oxytocin receptor gene (OXTR) variants and autism spectrum disorders (ASD) have been reported in earlier studies; in one of the studies associations with IQ and daily living skills were found additionally. Variations of the oxytocin receptor gene might also regulate affect, attachment and separation beyond the diagnostic borders of autism. We tested hypotheses of associations between positive and negative affects and social and emotional loneliness (285 adults), IQ (117 adolescents) and polymorphisms of the oxytocin receptor gene (OXTR rs53576, rs2254298 and rs2228485) in normal subjects. Individuals with the oxytocin OXTR rs53576 A/A genotype showed lower positive affect scores (F=5.532, df=1; p=0.019). This effect was restricted to males (F=13.098, df=1; p=0.00047). Haplotypes constructed with the three markers were associated with positive affect (p=0.0012), negative affect (p<0.0001) and emotional loneliness (p<0.0001). Non-verbal intelligence was significantly reduced in rs53576 A/A adolescents (T=2.247, p=0.027). Our findings support a role for the oxytocin receptor haplotypes in the generation of affectivity, emotional loneliness and IQ.
Inherited factor VII deficiency (FVIID) is a rare autosomal bleeding disorder. Subjects with reduced FVII activity and identified F7 gene mutation are registered in the International Greifswald registry of FVIID.[1][1] The mutation A294V is the most frequent among 717 FVIID patients in Central and
Factor X (FX) deficiency is a very rare haemostatic disorder. It is inherited in an autosomal recessive trait. Coagulation FX, the zymogen of the vitamin K dependent serine protease FXa, circulates in plasma as a two chain protein comprising a 17 kDa light chain covalently bound to a 45 kDa heavy chain. The gene encoding FX spanning about 25 kb genomic DNA is located at chromosome 13q34. It encodes 8 exons and 7 introns. The variable severity correlates poorly with laboratory phenotype. Whereas heterozygote carriers of an FX mutation very often are asymptomatic, homozygote or compound heterozygote carriers with a residual FX activity below 1% may suffer from severe bleedings. Homozygous FX deficiency is extremely rare (1 : 1 000 000). A rare complication of severe FX deficiency is an intracranial haemorrhage (ICH).
In this study, eight common polymorphisms associated with venous thrombosis (VT) and thrombophilia factors were analyzed in a Costa Rican case-control study. With the use of polymerase chain reaction (PCR) methods the polymorphisms were detected in 120 patients and 133 controls (mean age <40 years old). It was concluded that a high level of fibrinogen, antiphospholipid antibodies, family history, and the genotype 34LeuLeu of FXIII OR 0.42 (0.20-0.89) showed a significant effect on the risk of VT. Associations between the risk of VT and genetic polymorphisms have been established. Some of these polymorphisms are highly prevalent in Caucasians, but there is a significant geographic variation in their prevalence among different populations. The results of this study support the protective effect of FXIII Val34Leu polymorphism in VT. These findings are consistent with previous reports that included other populations.
Background: Both reduced postsynaptic dopamine D2 receptor function and the character variable self-directedness (SDD) are related to the level of alcohol consumption. We examined for interactions between DRD2 exon 8(rs6276), a polymorphism which has been associated with various alcohol-related phenotypes, SDD and alcohol consumption. Methods:A total of 144 male and 186 female probands with alcohol dependence or abuse diagnoses and without were included in the study. All subjects were assessed with the alcohol section of the Semi-Structured Assessment for the Genetics of Alcoholism and the Temperament and Character Inventory. Results: Male probands with A/A genotype reported significantly higher alcohol consumption in a typical week (ANOVA; p = 0.024); those with A/A genotype and low SDD showed particularly high consumption levels (interaction DRD2 × SDD: p = 0.019). Alcohol dependence/abuse (DSM-IV) but not nicotine dependence was also relevant for higher alcohol consumption (trend: p = 0.052). In the female group, only alcohol disorders predicted alcohol consumption. Conclusions:Our findings support a role for a gene-personality interaction of DRD2 exon 8 × SDD in alcohol consumption in males.
Two families with 'factor X(FX)-Riyadh' have been identified (one of them related to the originally reported family). Affected members of both families exhibit prolongation in prothrombin time (PT) with normal partial thromboplastin time (PTT) and low assay levels of FX, when measured by PT-based assay. They do not have clinical bleeding diathesis, regardless of the PT prolongation. FX genes of the affected family members were analyzed by sequence analysis. A novel missense mutation in exon 4 of the FX gene, which causes the Glu51Lys substitution in the first epidermal growth factor-like domain of FX was found. The Glu51Lys mutation represents a type II mutation with low FX coagulant activity in the extrinsic pathway and normal FX antigen levels. This mutation may result in disruption of the predicted H-bonding between residue Glu51 of FX and the Asn199 residue of the tissue factor (TF) in the FX/TF/factor VIIa ternary complex, producing the phenotype 'FX deficiency Riyadh', with prolonged PT and normal PTT.
Twin studies suggest a genetic influence upon perceived parenting. The D(2) dopaminergic receptor is involved in the modulation of social behaviors, and might influence parenting and its perception. A polymorphism (E8) in exon 8 of the D(2) receptor gene (DRD2) has been previously associated with alcoholism-related phenotypes. Similarly, the Pro385Ser variant of GABRA6, the polymorphic gene for GABA(A) receptor alpha6 subunit, has been associated with alcohol- and depression-related traits; and rat pups maintained a more immature GABAR phenotype after brief separation distress. The relationships among DRD2 (E8) and GABRA6 (Pro385Ser) polymorphisms, and perceived parenting were studied here. The association of DRD2 (E8) and GABRA6 (Pro385Ser) genotypes and perceived parental rearing behavior (short-EMBU; questionnaire concerning own memories concerning upbringing) were determined in 207 unrelated adults using multivariate analysis of variance. Temperaments (Temperament and Character Inventory; TCI) were included as covariates. Probands with DRD2 (E8) A/A genotype showed higher scores for father rejection (P = 0.011), parents overprotection (P = 0.021), and father overprotection (P = 0.016) in the total group. An interaction between DRD2 and GABRA6 genotypes on father rejection (P = 0.010) and parents rejection (P = 0.030) was also observed. Further analyses showed that these associations were restricted to the female subgroup only; however, secondary gender-specific analyses were not corrected for multiple testing. Our findings support a role for DRD2 (E8) and GABRA6 (Pro385Ser) in perceived parenting.
Letters to the Editor: Haemophilia A in a female caused by coincidence of a Swyer syndrome and a missense mutation in factor VIII gene -
Eight common polymorphisms of known myocardial infarction (MI) risk factors (factor V Leiden (FVL), factor V HR2 (FVHR2), factor II 20210G > A (FII), factor VII IVS7 (FVII IVS7), factor VII Arg353Gln (FVII), factor XIII Va134Leu (FXIII), Methylenetetrahydrofolate reductase C677T (MTHFR), Angiotensin Converting Enzyme (ACE)) and environmental risk factors were analyzed in a MI patients of Costa Rica. This case-control study included 186 MI subjects, 95 of them < or = 45 years and 201 age and sex matched controls. With the use of PCR method the polymorphisms were detected and through interviews additional information was collected. Hypercholesterolemia and smoking were associated with a significant risk in younger patients. High fibrinogen level was an important risk factor and interaction with smoking was detected. Mainly, the genotype 34LeuLeu of FXIII showed significant protective effect, (OR 0.32, 95% CI 0.13-0.80) while the other polymorphisms showed no significant difference between the cases and the controls. Carriers of FVII (OR 2.75, 95% CI 1.07-7.02) and FXIII (OR 4.20, 95% CI 2.03-8.67) polymorphisms showed interaction with fibrinogen in the statistical analysis. It was concluded that there was an important interaction between the common risk factors and the polymorphisms (FVII; FXIII) in the development of MI. This is one of the first reports in a Latin-American population dealing with these molecular markers and MI.
The prevalence of hyperhomocysteinemia and C677T MTHFR polymorphism was studied in various ethnic groups from Western Venezuela (60 Wayuu Indians, 42 italian immigrants and 77 Venezuelan mestizos) in relation with the prevalence of hyperhomocysteinemia and the C677T MTHFR polymorphism. Homocysteinemia was determined by polarized fluorescence immunoassay in an IMX system, serum folate was measured by radioimmunoanalysis and the MTHFR genotype was determined by PCR and restriction analysis. Hyperhomocysteinemia was defined as a value over 2 SD above the mean value for normal MTHFR (CC677) in each group. The prevalence of MTHFR variants (C677T and 677TT) was elevated in all ethnic groups (78% among the wayuu, 76% among Italians and 63% among mestizos) with a significant association between the concentrations of homocysteine and the levels of serum folate among the wayuu (p < 0.0001) and the mestizos (p < 0.001) only. Hyperhomocysteinemia was associated with MTHFR variants in 23% of the wayuu (OR: 6.17, CI 95: 0.74-51.36), 9.5% of the Italians (OR: 0.93, CI 95: 0.085-10.10) and 20.7 of the Venezuelans mestizos (OR: 5.2, CI 95: 1.08-24.90, p > 0.03). There was no relationship between hyperhomocysteinemia and folate deficiency in any of the groups studied. In conclusion, despite a high prevalence of C677T MTHFR variants in these ethnic groups of western Venezuela, the lack of no evidence of hyperhomocysteinemia combined with folate deficiency may imply that the nutritional status of these groups plays an important role in the control of hyperhomocysteinemia as a risk factor for cardiovascular disease.
We investigated the association between the factor V Leiden gene variant and carotid atherosclerosis in a cross-sectional study and explored possible associations between this gene variant and coronary artery disease (CAD) in a case-control study.The presence (n=1696) or absence (n=703) of carotid atherosclerosis were sonographically assessed among participants of the population-based Study of Health in Pomerania (SHIP). The case-control study included 1021 patients with severe CAD and 2791 healthy SHIP participants. The factor V Leiden gene variant was determined by PCR and MnlI digestion.Multivariable analyses revealed no independent association between the factor V Leiden gene variant per se and carotid atherosclerosis or CAD. In the cross-sectional study, there was an interaction between the factor V Leiden gene variant and serum LDL cholesterol in non-diabetics with respect to the risk of carotid atherosclerosis. In the case-control study a similar interaction was found for CAD. In both studies the atherosclerotic risk increased with rising serum LDL cholesterol concentrations in carriers of the factor V Leiden gene variant.The co-existence between the factor V Leiden gene variant and high serum LDL cholesterol is independently associated with the risk of atherosclerosis.
In this study we investigated the influence of the presence of the factor V HR2 haplotype, defined by the factor V gene mutation H1299R (FVHR2), on thrombin generation. Measurements were performed in platelet-poor plasma of individuals with factor V-HR2 or factor V-Leiden in comparison to a control group carrying none of these mutations. Coagulation was triggered by low concentrations of recombinant tissue factor in the presence of activated protein C. Thrombin generation was monitored by a fluorogenic substrate. The endogenous thrombin potential was calculated from the obtained curves. As a result we observed an increased thrombin generation both for individuals heterozygous and homozygous for FVHR2. The level of endogenous thrombin potential is in the same range as in samples of patients heterozygous or homozygous for FVLeiden. The results indicate that FVHR2 plays a role as a risk factor for venous thrombosis in homozygous patients through an increased thrombin generation. The association between different clinical manifestations in individuals with FVII deficiency and endogenous thrombin potential and the presence of FVHR2 was studied.
ZusammenfassungIn einer Übersicht werden einige molekulargenetische Aspekte der Gerinnungsfaktoren VII, VIII, IX und X dargestellt. Das Spektrum der Mutationen wird charakterisiert, das zu den genetisch bedingten Defekten Hämophilie A und B, Faktor-VII- und -X-Mangel führt. Für die Hämophilien A und B wird der genetische Beratung auf der Grundlage des X-chromosomalen Erbganges und der indirekten und direkten genomischen Analyse an ausgewählten Beispielen vorgestellt.Die Gene der Vitamin-K-abhängigen Serinproteasen Faktor VII und Faktor X sind auf dem Chromosom 13 lokalisiert. Mutationen führen zu autosomal-rezessiv vererbtem Faktor-VII- oder Faktor-X-Mangel. Das Mutationspektrum, die Rolle von Polymorphismen der Gene und das Spektrum der spontanen Blutungen dieser seltenen Blutungsleiden werden charakterisiert und Genotyp-Phänotyp-Korrelationen aufgezeigt.
An association between the factor V Leiden variant and an increased risk of pregnancy loss has been reported. Most previous studies were performed with clinically recruited patients and controls. This approach may cause selection bias. The present analysis was performed with the aim to investigate the association between the factor V Leiden mutation and the risk of stillbirth in a population-based sample. The Study of Health in Pomerania (SHIP) is a survey that was carried out in North East Germany. A random sample from the population aged 20 to 79 years was taken. The total SHIP population comprised 4,310 participants. The presence of the factor V Leiden variant was determined by PCR and Mnl I digestion. The presence of the factor V Leiden variant was neither associated with the number of pregnancies nor with the number of children per women. Data from 1,768 females who had at least one pregnancy with known outcome was available for the present analysis. Seventy-three women (4.1%) reported at least one stillbirth. Women with and without the factor V Leiden mutation did not differ with respect to the number of women with at least one stillbirth (OR for factor V Leiden variant 1.57; 95%-CI 0.76 - 3.25). Furthermore, the number of women with two or more stillbirths, the number of stillbirths per affected woman and the number of stillbirths per number of pregnancies per woman was similar between both genotype groups. In conclusion, there is no association between the factor V Leiden mutation and the risk of stillbirth in a representative population sample.