alexa α-Actinin-3 deficiency is associated with reduced bone mass in human and mouse.
Genetics & Molecular Biology

Genetics & Molecular Biology

Journal of Molecular Biomarkers & Diagnosis

Author(s): Yang N, Schindeler A, McDonald MM, Seto JT, Houweling PJ,

Abstract Share this page

Abstract Bone mineral density (BMD) is a complex trait that is the single best predictor of the risk of osteoporotic fractures. Candidate gene and genome-wide association studies have identified genetic variations in approximately 30 genetic loci associated with BMD variation in humans. α-Actinin-3 (ACTN3) is highly expressed in fast skeletal muscle fibres. There is a common null-polymorphism R577X in human ACTN3 that results in complete deficiency of the α-actinin-3 protein in approximately 20\% of Eurasians. Absence of α-actinin-3 does not cause any disease phenotypes in muscle because of compensation by α-actinin-2. However, α-actinin-3 deficiency has been shown to be detrimental to athletic sprint/power performance. In this report we reveal additional functions for α-actinin-3 in bone. α-Actinin-3 but not α-actinin-2 is expressed in osteoblasts. The Actn3(-/-) mouse displays significantly reduced bone mass, with reduced cortical bone volume (-14\%) and trabecular number (-61\%) seen by microCT. Dynamic histomorphometry indicated this was due to a reduction in bone formation. In a cohort of postmenopausal Australian women, ACTN3 577XX genotype was associated with lower BMD in an additive genetic model, with the R577X genotype contributing 1.1\% of the variance in BMD. Microarray analysis of cultured osteoprogenitors from Actn3(-/-) mice showed alterations in expression of several genes regulating bone mass and osteoblast/osteoclast activity, including Enpp1, Opg and Wnt7b. Our studies suggest that ACTN3 likely contributes to the regulation of bone mass through alterations in bone turnover. Given the high frequency of R577X in the general population, the potential role of ACTN3 R577X as a factor influencing variations in BMD in elderly humans warrants further study. Copyright © 2011 Elsevier Inc. All rights reserved. This article was published in Bone and referenced in Journal of Molecular Biomarkers & Diagnosis

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

  • 9th International Conference and Expo on Molecular & Cancer Biomarkers
    August 23-24, 2017 Birmingham, UK
  • 2nd International Conference on Medical Imaging and Diagnosis
    London, UK
  • 22nd International Conference on Cancer Drugs and Therapeutics
    Paris, France
  • International Conference on Oncology Nursing and Cancer Care
    Singapore City, Singapore
  • World Summit on Cell Signalling and Cancer Therapy
    Toronto, Canada
  • International Conference on Radiology and Imaging
    New York, USA

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version