Plant Molecular Biology

, Volume 64, Issue 5, pp 613–618

Increased calcium bioavailability in mice fed genetically engineered plants lacking calcium oxalate

  • Jay Morris
  • Paul A. Nakata
  • Michele McConn
  • Amanda Brock
  • Kendal D. Hirschi


Bioavailable calcium affects bone formation and calcification. Here we investigate how a single gene mutation altering calcium partitioning in the model forage crop Medicago truncatula affects calcium bioavailability. Previously, the cod5 M. truncatula mutant was identified which contains identical calcium concentrations to wild-type, but contains no oxalate crystals. In this study, equal number of male and female mice were randomly grouped and then fed one of four 45Ca-containing diets: M. truncatula extrinsically or intrinsically labeled, and cod5 extrinsically or intrinsically labeled. Absorption of the tracer was determined in the legs one day after consumption. The absorption was similar in the M. truncatula and cod5 extrinsically labeled diets; however, in the intrinsically labeled diets, calcium absorption was 22.87% (P < 0.001) higher in mice fed cod5. Our study presents the first genetic evidence demonstrating the nutritional impact of removing oxalate crystals from foods.


Calcium bioavailability Medicago truncatula Mice Oxalate crystal 





Calcium oxalate deficient

M. truncatula

Medicago truncatula




Standard error of the mean


Least squared means test


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Jay Morris
    • 1
    • 2
  • Paul A. Nakata
    • 2
  • Michele McConn
    • 2
  • Amanda Brock
    • 2
  • Kendal D. Hirschi
    • 1
    • 2
    • 3
  1. 1.Vegetable and Fruit Improvement CenterTexas A&M UniversityCollege StationUSA
  2. 2.Plant Physiology Group, United States Department of Agriculture/Agriculture Research Service, Children’s Nutrition Research Center, Department of PediatricsBaylor College of MedicineHoustonUSA
  3. 3.Department of Molecular and Human GeneticsBaylor College of MedicineHoustonUSA

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