To our knowledge this is the first study that has examined the effect of an athlete's ACE genotype on their actual performance during an ultra-endurance race. The I allele of the ACE gene was associated with the endurance performance of the fastest 100 South African-born finishers in these triathlons.

We have previously shown that the insertion allele of the angiotensin-converting enzyme (ACE) gene was over-represented in the fastest South-African-born finishers of the South African Ironman Triathlons. As ACE is a component of the skeletal muscle kallikrein-kinin system (KKS), the aim of this study is to determine if there are any further associations between polymorphisms within the BDKRB2 and NOS3 genes, which encode for the KKS components, bradykinin beta(2) receptor and nitric oxide synthase, respectively, and ultra-endurance performance during the Ironman Triathlons. Four-hundred and forty-three male Caucasian triathletes who completed the 2000 and/or 2001 South African Ironman Triathlons and 203 healthy Caucasian male control subjects were genotyped for the functional -9/+9 polymorphism within exon 1 of the BDKRB2 gene and the G894T NOS3 gene polymorphisms. The BDKRB2 -9/-9 genotype occurred at a significantly higher frequency when the triathlete group (27.0%) was compared with the control group (19.3%, P=0.035). When divided into tertiles, there was also a significant linear trend for the NOS3 GG genotype distribution among the fastest (35.0%), middle (40.4%) and slowest (46.9%) finishers (P=0.039). The overall finishing times of the triathletes with an NOS3 GG genotype together with a BDKRB2 +9 allele were significantly slower than those with other genotype combinations (P=0.001). The NOS3/BDKRB2 genotype (beta=-0.150, B=-31.48, P=0.002), together with body mass index and age, accounted for 14.6% of the variance in the overall race time for the triathlon. In conclusion, both the NOS3 and BDKRB2 genes are associated with the actual performance during the Ironman Triathlons.

No abstract

Studies in several populations have indicated that genetic variation at the apolipoprotein E (apoE) structural locus influences the risk of coronary artery disease (CAD) and myocardial infarction (MI). This study aimed at investigating whether apoE polymorphism has an allelic and/or genotypic impact on the risk of MI in Greek patients with CAD. We compared apoE gene polymorphism in a group of patients with angiographically confirmed CAD but not MI [CAD/MI (-)-group, n = 143] and a group of age and sex-matched CAD patients who had experienced a non-fatal Ml [CAD/MI (+)-group, n = 124]. The patients were also compared with a group of healthy younger individuals (n = 240) with no family history of CAD. The apoE genotype distribution differed significantly between the two groups of CAD patients (p = 0.02). The epsilon2 allele was 5.3-fold less frequent in the CAD/ MI (+)-group compared with the CAD/MI (-)-group (1.2% vs. 6.3%, p = 0.01). The frequency of the epsilon2 allele in healthy subjects was 8.1%, which is 6.8-fold higher than in CAD/MI (+)-patients (p = 0.001) and twice as high compared with all CAD patients (p = 0.02). No differences in epsilon4 allele frequencies were observed between CAD/MI (+)- and CAD/MI (-)-patients (10.9% vs. 9.8%), or between patients with CAD and healthy subjects (10.3% vs. 10.2%). In summary, the epsilon4 allele was not found to be associated with an increased risk for CAD or MI. In contrast, a negative association of the epsilon2 allele with Ml was observed among Greek patients with CAD.

Practicing forensic scientists who are called to provide expert witness testimony are often asked to explain both the presence and the absence of DNA on objects that have been handled by perpetrators with bare hands. Unwashed hands, depending on what they have come in contact with previously, may become the vehicle of both primary and secondary transfer of DNA. In this study, we investigated the propensity of primary and secondary transfer of DNA from unwashed bare hands of 128 individuals onto plastic tubes. Our experiments, carried out in triplicate, have shown that DNA was not detected on all the touched tubes, secondary transfer of DNA, through unwashed hands, was small, and in the majority of cases primary DNA transfer could be distinguished from secondary DNA transfer. A statistically significant association was demonstrated between percent DNA profile deposited on plastic tubes, through unwashed hands, and the age of male individuals.

Thirst is regulated by a complex interaction of signalling pathways within the central nervous system, including components of the renin-angiotensin and kalikrein kinin systems, as well as the serotonergic pathways. The aim of this study was to determine whether there were any associations between polymorphisms within the ACE, BDKRB2, NOS3 and/or 5-HTT genes with weight changes during the 2000 and 2001 226 km South African Ironman Triathlons. Pre- and post-race serum [Na(+)] and body weights, as well as genotype data, were collected from 428 (61.1%) Caucasian male triathletes who were divided into three groups according to their relative weight loss during the triathlon (0-3, 3-5 and >5%). There was a significant linear trend for the distribution of both the BDKRB2 +9/+9 genotype and the 5-HTT SS genotype between the three weight loss groups, with the >5% group having the highest percentage of athletes with the +9/+9 genotype (chi(2)=5.3, P=0.021) and the highest percentage of athletes with the SS genotype (chi(2)=5.8, P=0.016). Likewise, the >5% group had the highest percentage of athletes with the combined SS 5-HTT and/or +9/+9 BDKRB2 genotypes (chi(2)=7.4, P=0.007). In conclusion, the functional SS genotype of the serotonin transporter-linked polymorphic region (5-HTTLPR) within the 5-HTT gene and the functional +9/+9 genotype of the BDKBR2 gene were associated with larger weight losses during the Ironman Triathlons. These findings suggest the involvement of the serotonergic pathways in the control of thirst and drinking behaviour and provide further evidence for the dipsogenic effect of circulating bradykinin.

SummaryAlpha-actinins are major structural components of the Z-discs in skeletal muscle. Alpha-actinin 3 is encoded by the ACTN3 gene and is expressed only in type II muscle fibres. Homozygosity for the nonsense mutation, 577X, within ACTN3 results in deficiency of α-actinin-3 but does not result in an abnormal muscular phenotype. Previous research has found an association of the 577R allele with sprinting and/or power performance. It has also been suggested that the 577X allele may confer an advantage during endurance events. Four hundred and fifty seven Caucasian male triathletes who completed either the 2000 and/or 2001 226 km South African Ironman Triathlons, and 143 Caucasian controls, were genotyped for the R577X mutation within the ACTN3 gene. There were no significant differences in either the genotype (P = 0.486) or allele (P = 0.375) frequencies within the fastest, middle of the field or slowest Caucasian male finishers and the control population. In conclusion, the R577X polymorphism within the ACTN3 gene was not associated with ultra-endurance performance in the 2000 and 2001 South African Ironman Triathlons.

No abstract