Developmental and Acquired Diseases of the Bone

Question 1

Marfan syndrome is caused by a defect in which protein?

Answer 1

Fibrillin-1

Question 2

What is the inheritance pattern of Marfan syndrome?

Answer 2

Autosomal dominant

Question 3

Which gene is mutated in Marfan syndrome?

Answer 3

FBN1

Question 4

What are the four organ systems that can be involved in Marfan syndrome?

Answer 4

Skeletal, cardiovascular, ocular, and skin

Question 5

What are the common skeletal abnormalities in patients with Marfan syndrome?

Answer 5

Tall stature, long extremities and digits, joint laxity, spinal and chest deformities

Question 6

What are the common ocular abnormalities in patients with Marfan syndrome?

Answer 6

Ectopia lentis (bilateral sublaxation or dislocation of the lens)

Question 7

What are the common cardiovascular abnormalities in patients with Marfan syndrome?

Answer 7

Mitral valve prolapse, aortic dilation (can lead to aortic dissection)

Question 8

What is the function of fibrillin-1?

Answer 8

Provide scaffolding in for tropoelastin in ECM, providing structural integrity in connective tissues; regulation of TGF-β signaling pathway

Question 9

What causes Ehlers-Danlos syndromes?

Answer 9

Defects in collagen synthesis or structure, leading to inadequate tensile strength of collagen-rich tissues

Question 10

What are the two primary symptoms of Ehlers-Danlos syndromes?

Answer 10

Joint hypermobility and skin hyperelasticity