Presence Of Met Allele Research Articles

Aerobic Exercise Increases Parasympathetic Activity on BDNF Genetic Variant Val66Met Carriers

Aerobic exercise training (ET) can improve autonomic control, we aimed to investigate the influence of BDNF variant polymorphisms over the sympatho‐vagal balance, pre and post ET in police officers of São Paulo's State Military Police. We hypothesized: 1) presence of the allele Met is associated with a higher rest heart rate (restHR) and lower heart rate variability (HRV), 2) ET will reverse this impairment on the carriers of the Val66Met polymorphism. 80 healthy male (25±4 yrs) underwent to ET on a running track for 5 months. Autonomic control was assessed by the HRV (ECG) at rest. BDNF genotyping resulted in 27.5% (n=22) of Val66Met and 72.5% (n=58) of Val66Val individuals. In the pre ET period, Val66Met presented higher restHR compared with Val66Val (86±13vs.68±6 bpm; p<0.05). HRV was similar between groups. ET similarly improved functional capacity in Val66Met and Val66Val. The pre ET difference on restHR disappeared (67±4 vs. 68±11 bpm; p>0.05). Further analyses showed negative association between restHR changes and oxygen consumption increases (r=‐0.52 e p<0.05). The presence of Met allele could impair parasympathetic modulation of restHR, which is abolished by ET.

Brain‐derived neurotrophic factor and risk for primary adult‐onset cranial‐cervical dystonia

Adult-onset dystonia may be related, amongst other factors, to abnormal neuronal plasticity in cortical and subcortical structures. Brain-derived neurotrophic factor is a major modulator of synaptic efficiency and neuronal plasticity. Recent works documented that a single nucleotide polymorphism (SNP) of the BDNF gene, the Val66Met SNP, modulates short-term plastic changes within motor cortical circuits. In this study we aimed at exploring the effect of this SNP upon the risk of developing common forms of primary adult-onset dystonia. We explored the influence of the Val66Met SNP of the BDNF gene on the risk of cranial and cervical dystonia in a cohort of 156 Italian patients and 170 age- and gender-matched healthy control subjects drawn from the same population. The presence of the rare Met allele was not significantly associated with the diagnosis of dystonia (age- and gender-adjusted odds ratios of 1.22, P = 0.38). The study had a >90% power to detect a 50% change in the risk of developing cranial-cervical dystonia associated with the presence of the Met allele. Moreover, there was no relationship between Val66Met SNP and age at dystonia onset or type of dystonia. Our data do not support the common variant Val66Met of the BDNF gene as an etiologic factor shared by the various forms of primary adult-onset dystonia.

Association between platelet glycoprotein Ibalpha genotype and ischemic cerebrovascular disease.

Platelets play pivotal roles in the development of ischemic cerebrovascular disease (CVD). The platelet glycoprotein (GP) Ib/IX/V complex is a receptor for von Willebrand factor, which plays a major role in the initial phase of platelet activation under high shear stress conditions. This study was designed to investigate the association between a genetic variation of this receptor and the prevalence of CVD. Two hundred patients with ischemic CVD, as confirmed by brain CT and/or MRI, and 317 age- and sex-matched control subjects without clinical evidence of CVD or cardiovascular disease were analyzed for their genotype frequencies of the (145)Thr/Met dimorphism of the alpha-chain of GPIb (GPIbalpha). Genotypes with (145)Met (T/M and M/M) were more frequently found in the CVD patients (26.5%) than in control subjects (14.2%, P=0.0005). The genotype effect was more obvious in those <60 years of age or without acquired cardiovascular risk factors. The odds ratio for nonsmoking women <60 years of age was 10. 6 (95% confidence intervals, 2.2 to 51.7). Although the number of patients studied was small (n=24), transient ischemic attack showed the highest odds ratio (4.3, P=0.0004), followed by lacunar infarction (OR=2.2, P=0.0024) and atherothrombotic infarction (OR=1. 5, P=0.3143). Logistic regression analysis revealed that the presence of Met-allele was independently associated with CVD. Our study suggests that the platelet GPIbalpha genotype is a genetic risk factor for ischemic CVD.