Six at Sixty. Commentary on osteogenesis imperfecta 1975-2025
1Genomic Medicine, University of Sydney Clinical School, Children's Hospital, Westmead, New South Wales, Australia david.sillence@sydney.edu.au.
Journal of Medical Genetics
|May 27, 2025
Summary
Osteogenesis imperfecta (OI) is genetically heterogeneous, not caused by a single gene as previously thought. This finding paved the way for understanding bone fragility disorders and precision medicine approaches.
Area of Science:
- Genetics
- Orthopedics
- Medical Research
Background:
- Osteogenesis imperfecta (OI) was historically considered a single-gene disorder.
- The prevailing hypothesis linked all OI presentations to variations in a single gene locus, potentially related to type I collagen.
- Limited understanding existed regarding the genetic heterogeneity of bone fragility disorders.
Purpose of the Study:
- To investigate the diverse clinical manifestations of osteogenesis imperfecta (OI) and familial bone fragility.
- To challenge the prevailing view of OI as a single-gene disorder.
- To establish the genetic heterogeneity of OI.
Main Methods:
- Conducted a whole-of-population study in Victoria, Australia, between 1975 and 1977.
- Examined clinical presentations and manifestations of bone fragility.
- Analyzed patient data to identify patterns and variations.
Main Results:
- Concluded that OI is genetically heterogeneous, with multiple causative genes.
- Demonstrated that OI presentations are not solely due to variations in a single gene.
- Identified the need for further biochemical and genomic research.
Conclusions:
- OI results from pathological variants in over 20 genes.
- Related forms of familial osteoporosis and bone fragility syndromes involve variants in additional loci.
- A dyadic nosology aids diagnosis, treatment, and research in OI, supporting precision medicine.
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