Collagen Structure and Disorders

A 28-year-old woman from Kerala presents with recurrent joint dislocations, hyperextensible skin, and easy bruising. On examination, she has marked hypermobility of all joints and translucent, velvety skin with visible veins. Biochemical analysis reveals defective lysyl oxidase activity. Which type of collagen is primarily affected in this condition?

A 5-year-old boy from Delhi presents with a 2-year history of progressive bone pain, short stature, and blue-tinged sclera. His mother reports multiple fractures from minor trauma. Serum alkaline phosphatase is elevated. X-rays show generalized osteopenia with thin cortices and multiple healed fractures. Genetic testing reveals a mutation in COL1A1. Which biochemical defect in collagen synthesis best explains the skeletal fragility in this patient?

A 35-year-old man with a known diagnosis of osteogenesis imperfecta (OI) presents with recurrent bone fractures and blue sclerae. His father had similar symptoms and died of a basilar skull fracture following minor head trauma. To confirm the diagnosis and determine the severity of the genetic defect, which investigation is most appropriate?

In osteogenesis imperfecta, mutations in genes encoding type I collagen result in which primary structural defect?

A 28-year-old woman presents with a 2-year history of progressive joint pain, skin hyperextensibility, and easy bruising. Physical examination reveals hypermobile joints and velvety skin texture. She reports a family history of similar symptoms in her mother. Which investigation is most appropriate to confirm the suspected diagnosis of Ehlers-Danlos syndrome (EDS) Type III (vascular EDS)?