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Background: Hereditary haemochromatosis, a disease that affects iron metabolism, progresses with a greater or lesser tendency to induce iron overload, possibly leading to severe organ dysfunction. Most elite endurance athletes take iron supplements during their active sporting life, which could aggravate this condition. Objective: To determine the prevalence and discuss potential clinical implications of mutations of HFE (the gene responsible for hereditary haemochromatosis) in endurance athletes. Methods: Basal concentrations of iron, ferritin, and transferrin and transferrin saturation were determined in the period before competition in 65 highly trained athletes. Possible mutations in the HFE gene were evaluated in each subject by extracting genomic DNA from peripheral blood. The restriction enzymes SnaBI and BclI were used to detect the mutations 845G-->A (C282Y) and 187C-->G (H63D). Results: Our findings indicate a high prevalence of HFE gene mutations in this population (49.2%) compared with sedentary controls (33.5%). No association was detected in the athletes between mutations and blood iron markers. Conclusions: The findings support the need to assess regularly iron stores in elite endurance athletes. [ABSTRACT FROM AUTHOR]

Despite progress made in the treatment of tobacco dependence, currently available treatments are eff ective for only a fraction of smokers. The aim of this study was to evaluate the association between the effectiveness of treatment with nicotine or bupropion in heavy smokers (n = 70), and 6 candidate polymorphisms in CYP2A6 , 5-HTT and HTR2A genes. Analysis revealed a significant association between "favourable" genotype combination carriers ( CYP2A6 "slow metabolizer" or 5HTT L-allele or HTR2A-1438GG) and nicotine treatment outcome (OR = 2.69, 95 % CI = 1.28-5.64). Genetic variations in CYP2A6 gene or genotypes associated with reduced synaptic serotonin activity may influence the success of smoking cessation treatment. [ABSTRACT FROM AUTHOR]

The -174 G/C polymorphism [rs1800795] of the IL6 gene is a candidate to explain individual variations in health and exercise related phenotypes. We compared -174 G/C genotypic and allelic frequencies in three groups of men of the same Caucasian (Spanish) descent: elite endurance athletes (cyclists, runners; n=100); elite power athletes (jumpers, throwers, sprinters; n=53) and non-athletic controls (n=100). The frequency of the GG genotype (P=0.030) and G allele (P=0.026) was higher in the power athletes group compared with the control group. The frequency of the GG genotype (P=0.033) and G allele (P=0.013) was also higher in the power athletes group compared with the endurance athletes group. The odds ratio of being a power athlete if the subject had the GG genotype (dominant model) was 2.471 (95% confidence interval: 1.242-4.915) compared to the control group or the endurance athlete group. We did not find differences between the control and endurance athlete groups. In summary, our findings suggest that the G allele of the IL6 -174 G/C polymorphism might favour sprint/power sports performance. [ABSTRACT FROM AUTHOR]

We studied the association of ACE and ACTN3 polymorphisms with skeletal muscle phenotypes (i.e. upper and lower body muscular strength and functional tests) in Spanish nonagenarian subjects [n=41, 33 women, 8 men, age: 90-97 years]. Mean values of the study phenotypes were not significantly different (all P>0.05) between ACE and ACTN3 genotypes. The analyses of the combined effects between genotypes (ACE DD & ACTN3 RR/RX vs. ACE II/ID & ACTN3 XX) did not yield any significant difference. Our data suggest that, in the elderly, the influence of genetic factors on muscle phenotype traits is not reducible to a Few single polymorphisms, including ACE and ACTN3 variants. [ABSTRACT FROM AUTHOR]

Background: McArdle disease is an uncommon metabolic disorder usually characterized by marked exercise intolerance although great individual variability exists in its phenotypic manifestation. Objective: The purpose of this study was to determine the association between angiotensin-converting enzyme (ACE) genotypes and indices of exercise capacity (peak oxygen uptake (VO2PEAK), ventilatory threshold (VT) and gross mechanical efficiency (GE)) in patients with McArdle disease. Based on previous research, it was hypothesized that the / allele might favourably influence exercise capacity. Methods: Forty-four Spanish patients (23 males, 21 females) and 44 age-matched and gender-matched controls (23 males, 21 females) performed a graded cycle-ergometer test until exhaustion (for VO2PEAK and VT determination) and a 12 mm constant-load test at the power output eliciting the VT (for GE determination). Results: No significant difference )p>0.05) was found in indices of exercise capacity between ID + II genotypes and DD homozygotes in the group of male patients, male controls and female controls. However, in the group of female patients, the ID + II group (n = 11) had a higher VO2PEAK than DD homozygotes (n = 10) (15.8 (SEM 1.6) ml/kg/min versus 11.9 (SEM 0.9) ml/kg/min, respectively; p<0.05). Conclusions: The / allele of the ACE gene is associated with a higher functional capacity in female patients, and might partly explain the individual variability in the phenotypic manifestation of McArdle disease. [ABSTRACT FROM AUTHOR]

Atopic-related factors, humoral and mucosal immunoglobulins (Ig), and cortisol were measured in 17 professional cyclists competing in the 2003 Vuelta a España (a three-week multi-stage race). Venous blood and saliva samples were obtained the morning before the start of the race (T0), on the first rest day after 10 days of racing (T1), and before the start of the last stage after 21 days of racing (T2). Atopic-related factors, IgE, eosinophil cationic protein (ECP), and eosinophils, were significantly altered during the race. Serum IgE (T1: + 10%) and ECP (salivary, T1: 113% and serum, T2: 155%) were significantly increased, while eosinophils (T1: - 32%, T2: - 55%) were significantly lower, than pre-race levels. Salivary sIgA secretion rate was significantly decreased at T2 (- 36%). Pearson product-moment correlations revealed a modest correlation between salivary sIgA and salivary ECP (T1: r = 0.30; T2: r = 0.48; p < 0.01). Serum IgM, total IgG, IgG1, IgG2, IgA levels, at T1 and T2, and cortisol at T2, were significantly lower than pre-race levels. In conclusion, the elevation in IgE and ECP suggests an up-regulation of atopic-related factors in professional cyclists participating in the Vuelta a España. The correlation between salivary sIgA and salivary ECP indicates a role for sIgA in mediating mucosal inflammation. The alterations in Ig levels may indicate Ig isotype switching. An increasing state of hormonal fatigue may have influenced the observed immune alterations. [ABSTRACT FROM AUTHOR]

We aimed to replicate the original findings by Eynon etal. [4] showing an association between the T alíele of the CNB3 C825T polymorphism and elite endurance athletic status, in larger cohorts and in other ethnicities. We compared allelic and genotypic frequencies of the CNB3 C825T polymorphism among non-athletic controls (N=340), elite endurance athletes (N = 174), and power athletes (N = 134). The population sample included participants from 2 different ethnic/geographic backgrounds (Israel and Spain). We observed no significant differences in genotypic and allelic frequencies between countries or groups (all P>0.1). The odds ratio (OR) of being an endurance athlete if the subject had a T alíele was 0.841 (95%CI: 0.638-1.110) compared to the control group and 1.047 (95% CI: 0.751-1.461) compared to the power group. Our findings support the need to corroborate genotype :phenotype associations in the field of sports genetics with the largest possible population samples, including populations of different ethnic backgrounds. [ABSTRACT FROM AUTHOR]

In this study, allele and genotype frequencies of the ADRB1 Arg389Gly (rs1801253), ADRB2 Gly16Arg (rs1042713) and Gln27Glu (rs1042714), and ADRB3 Trp64Arg (rs4994) variations were compared in the following three groups of Spanish (Caucasian) men: (1) world-class endurance athletes (E; runners and cyclists, n=100), (2) elite power athletes (P; sprinters, jumpers and throwers, n=53) and (3) non-athletic controls (C; n=100). No significant differences were observed in genotype and allele distributions among the study groups except for the ADRB3 Trp64Arg polymorphism in E versus C (27% vs 8% of carriers of the Arg allele in E and C, p<0.001; frequency of the minor Arg (C) allele of 14% vs 4% in E and C, p=0.001). Heterozygosity for the ADRB3 Trp64Arg polymorphism seems to be associated with elite endurance performance, while other variants of the [beta]-adrenergic receptors' genes do not seem to significantly influence top-level sports performance, at least in athletes of Spanish origin. [ABSTRACT FROM AUTHOR]

The muscle protein alpha-actinin-3 (ACTN3) is normally thought to be expressed in type II muscle fibres and to be necessary for high-power, high-velocity muscle contractions, such as those typically seen in speed/power athletes. The authors report the case of a Spanish elite long jumper (two times Olympian, personal best of 8.26 m) whose genotype for the ACTN3 gene is 577XX (ACTN3 deficient). These data suggest that there might be notable exceptions to the concept that ACTN3 is the 'gene for speed'. [ABSTRACT FROM AUTHOR]