Submitted on October 11, 2002
Accepted on December 12, 2002
The Na+, K+-ATPase 
2 Gene and Skeletal Muscle Characteristics in Response to Long-Term Overfeeding
Olavi Ukkola1, Denis R Joanisse2, Angelo Tremblay2, and Claude Bouchard3*
1 Human Genomics Laboratory, Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA; Department of Internal Medicine and Biocenter Oulu, University of Oulu, Oulu, Finland
2 Physical Activity Sciences Laboratory, Laval University, Ste-Foy, Quebec, Canada
3 Human Genomics Laboratory, Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA
* To whom correspondence should be addressed. E-mail: Bouchac{at}PBRC.edu.
The role of Na+, K+-ATPase 
2 gene Bgl II polymorphism in the changes of skeletal muscle metabolic properties after a 100-day overfeeding protocol conducted with 12 pairs of monozygotic twins is reported. The activities of oxoglutarate dehydrogenase (OGDH) and phosphofructokinase (PFK) were determined from muscle biopsies. A larger increase in the total fat mass (127% vs. 61%)(p<0.05) and LDL-cholesterol (20% vs. 0.7%) (p=0.05) in 8.0 / 8.0 kb (3.3 kb negative (-); n=14) than in 8.0 / 3.3 + 3.3 / 3.3 kb (3.3 kb positive (+); n=10) subjects was observed. OGDH activity decreased in 3.3 kb - (-15%) while PFK (+26%) as well as the PFK / OGDH ratio (90%) increased. In contrast, among 3.3 kb +, OGDH increased (+54%) together with a decrease in PFK (-1%) and the PFK / OGDH ratio (-5%). These changes were significantly different between genotypes (p from < 0.05 to < 0.01). In conclusion, fat mass, LDL-cholesterol, the amount of AVF, and skeletal muscle glycolytic to oxidative enzyme ratio increased more in the alpha 2 gene 3.3 kb negative subjects with overfeeding, suggesting more unfavorable metabolic changes compared to the 3.3 kb + subjects.
