Bone Fragility Disorders Related to Mendelian Inheritance

Abstract

Genetics is a discipline of study that can be traced back to Gregor Johann Mendel, making it unique among other fields. Mendel\'s investigations led to the discovery of three inheritance rules, now known as Mendel\'s rules of inheritance or Mendelism. The bone is unique among structural materials in that it can self-repair and modify its properties and configuration in reaction to changes. It also contains four types of cells: osteoblasts, bone lining cells, osteocytes, and osteoclasts. This study examines bone fragility illnesses linked to Mendelian inheritance. We briefly cover illnesses such as osteoporosis, osteopetrosis, osteogenesis imperfecta, and current results. Investigating Mendelian laws led to a better understanding of inherited bone fragility syndromes. Bone fragility is a pathological condition characterized by changed mineralized bone mass and degradation of bone tissue, leading to reduced bone strength and increased fracture risk, even without high-impact trauma. Primary osteoporosis is the leading cause of bone fragility in the older population. Bone fragility can occur at any age due to congenital uncommon bone metabolic illnesses caused by inherited genetic defects that disrupt proper bone structure.

Introduction

I. Gregor Mendel and the Laws of Inheritance

In the mid-19th century, Gregor Mendel laid the foundation of modern genetics through his hybridization experiments on Pisum sativum (pea plants). His work led to two key principles:

• Law of Dominance: Traits are governed by paired "factors" (now known as genes). In heterozygous pairs, dominant traits mask recessive ones.

• Law of Segregation: During reproduction, allele pairs separate, and offspring receive one allele from each parent. This explains the 3:1 ratio observed in the second generation of Mendel’s pea plants.

II. Bone Fragility Disorders

A. Osteogenesis Imperfecta (OI)

OI, or brittle bone disease, is a rare genetic connective tissue disorder characterized by:

• Recurrent fractures, low bone mass, and skeletal abnormalities

• Symptoms such as blue sclera, hearing loss, and dentinogenesis imperfecta

• Varying severity; fractures can occur in childhood or adulthood

• Caused by mutations affecting collagen production

B. Osteoporosis

A common bone fragility disorder, especially in postmenopausal women, defined by:

• Low bone mineral density (BMD) and increased fracture risk

• Fractures typically occur at the spine, hip, wrist, and humerus

• Caused by aging, genetics, and lifestyle

• Recent innovation: A diagnostic device using blood sampling to measure k-POSTN, a periostin fragment specific to bone fragility. This offers better diagnosis compared to bone densitometry, especially in diabetic patients.

C. Osteopetrosis

Also known as "marble bone disease", this rare genetic disorder results in:

• Abnormally dense bones due to impaired osteoclast function

• Symptoms include hematopoietic insufficiency, nerve compression, and tooth issues

• Autosomal recessive (ARO) is the most severe type, often appearing in infancy

• Treatment: Severe cases may benefit from hematopoietic stem cell transplantation

• Genetic diversity in osteopetrosis includes autosomal dominant, recessive, and X-linked forms; novel mutations are still being discovered

• A milder form, Intermediate ARO (IARO), presents with features like fractures, osteomyelitis, and enlarged liver and spleen

Conclusion

Known as the \"Father of Genetics,\" Gregor Johann Mendel, an Austrian monk, was the first to finish experiments and study heredity for any reason (1822-1884). He provided the two well-known laws of inheritance, the Law of Segregation and the Law of Dominance. Important bodily processes like movement, storing calcium and phosphate, and housing bone marrow are all facilitated by the human bone. Although bone appears to be inert, it is actually a dynamic organ that is constantly being reabsorbed by osteoclasts and renewed by osteoblasts. Although inheritance varies among diseases, the bone disorders under discussion are linked to mendelism. In rare instances, they may follow X-linked patterns, or they may be autosomal dominant or autosomal recessive. This paper accessed all routes wherein mendelian inheritance and roles of Mendel’s laws contributed to similar characteristics in bone fragility disorders like osteoporosis and osteopetrosis.

References

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Copyright

Copyright © 2025 Jia Jaison. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.