Question

Marfan syndrome and Ehlers-Danlos syndrome are both associated with defects of connective tissue. How do they occur, and what are the signs/symptoms?

a) Marfan syndrome results from a mutation in fibrillin-1; Ehlers-Danlos syndrome results from a defect in collagen synthesis; both present with hypermobility of joints
b) Marfan syndrome results from a defect in collagen synthesis; Ehlers-Danlos syndrome results from a mutation in fibrillin-1; both present with joint stiffness
c) Both syndromes result from mutations in collagen genes; Marfan syndrome presents with joint hypermobility, while Ehlers-Danlos syndrome presents with joint stiffness
d) Both syndromes result from mutations in elastin genes; Marfan syndrome presents with hypermobility, while Ehlers-Danlos syndrome presents with joint stiffness

Answer 1

Marfan syndrome is caused by a mutation in the gene for fibrillin-1, while Ehlers-Danlos syndrome is associated with defects in collagen synthesis. Both can exhibit joint hypermobility as a symptom, differentiating them from disorders that result in joint stiffness or mutations in elastin genes.

Step-by-step explanation:

Marfan syndrome and Ehlers-Danlos syndrome are both genetic disorders that affect connective tissue, but they have different underlying genetic causes and manifestation of symptoms. Marfan syndrome results from a mutation in the gene for fibrillin-1, a glycoprotein essential for the structure of microfibrils within the connective tissue. This mutation can lead to symptoms such as long limbs and fingers, lens dislocation, and cardiovascular issues.

On the other hand, Ehlers-Danlos syndrome is associated with defects in collagen synthesis. Types of collagen, like type-III, can be deficient due to mutations in collagen genes or issues with enzymes like hydroxylase that are important in the synthesis process. This leads to symptoms like hypermobility of joints, skin elasticity, and vulnerability of vessels and organs. Hence, the correct answer to the student's question would be Option A.