A polymorphism in the alpha2a-adrenoceptor gene and endurance athlete status.
OBJECTIVE
In a case control study, we examined the allelic frequencies and genotype distributions of two restricted fragment length polymorphisms (RFLP) in the alpha-2A-adrenoceptor gene (ADRA2A) and beta-2-adrenoceptor gene (ADRB2) among elite endurance athletes (EEA) and sedentary controls (SC).


METHODS
The EEA group included 148 Caucasian male subjects recruited on the basis that they had a VO2max > 74 mL O2 x kg(-1) x min(-1). The SC group comprised 149 unrelated sedentary male subjects, all Caucasians, from the Quebec Family Study. After digestion with the restriction enzymes Dra I (ADRA2A) and Ban I (ADRB2), Southern blotting and hybridization techniques were used to detect the mutations in the two ADR genes, which are encoded on chromosomes 10 (q24-26) and 5 (q31-32), respectively.


RESULTS
For the Dra I ADRA2A RFLP, we observed a significant difference in genotype distributions between the two groups (P = 0.037). A higher frequency of the 6.7-kb allele was observed in the EEA group compared with the SC group (P = 0.013). No statistically significant difference was found between groups for the Ban I ADRB2 polymorphic site. Genotype frequencies for both genes in both groups were in Hardy-Weinberg equilibrium.


CONCLUSIONS
In summary, we found evidence that ADRA2A gene variability detected with Dra I is weakly associated with elite endurance athlete status, and we conclude that genetic variation in the ADRA2A gene or a locus in close proximity may play a role in being able to sustain the endurance training regimen necessary to attain a high level of maximal aerobic power.
Wolfarth
B
B
Physical Activity Sciences Laboratory, Faculty of Medicine, Laval University, Ste-Foy, Québec, Canada.
Rivera
M A
MA
Oppert
J M
JM
Boulay
M R
MR
Dionne
F T
FT
Chagnon
M
M
Gagnon
J
J
Chagnon
Y
Y
Perusse
L
L
Keul
J
J
Bouchard
C
C
D000483:Alleles; D015139:Blotting, Southern; D016022:Case-Control Studies; D006801:Humans; D008297:Male; D010807:Physical Endurance; D012150:Polymorphism, Restriction Fragment Length; D018341:Receptors, Adrenergic, alpha-2 / Q000235:genetics*; D013177:Sports; D044465:White People / Q000235:genetics
D018341:Receptors, Adrenergic, alpha-2