Condition caused by deficiency of fibrillin 1 is?
## **Core Concept**
The question tests knowledge on the association between specific genetic deficiencies and their resultant clinical conditions, focusing on fibrillin 1. Fibrillin 1 is a protein crucial for the formation of elastic fibers found in connective tissue.
## **Why the Correct Answer is Right**
The correct answer, **Marfan syndrome**, is a genetic disorder that affects the body's connective tissue. It is caused by mutations in the gene that encodes fibrillin 1 (FBN1). This protein plays a vital role in the formation of elastic fibers found in connective tissue. The deficiency or malfunction of fibrillin 1 leads to the characteristic features of Marfan syndrome, which include tall stature, long limbs and digits, heart problems (especially with the aorta), and vision issues.
## **Why Each Wrong Option is Incorrect**
- **Option A:** Ehlers-Danlos syndrome is a group of disorders that affect connective tissues supporting the skin, bones, blood vessels, and many other organs and tissues. While it does affect connective tissue, it is primarily associated with defects in collagen synthesis or structure, not fibrillin 1.
- **Option B:** Osteogenesis imperfecta, also known as brittle bone disease, is a condition characterized by bones that break easily, often with little or no apparent cause. It is usually caused by mutations in the genes that encode type I collagen, not fibrillin 1.
- **Option C:** This option seems to be missing but based on the correct answer being Marfan syndrome, any other condition not directly linked to fibrillin 1 deficiency would be incorrect.
## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that Marfan syndrome can lead to serious cardiovascular complications, including aortic root dilatation and aortic regurgitation. Early diagnosis and management are crucial to prevent such complications. A classic feature that might be tested is the presence of ectopia lentis (lens dislocation) and the tall stature with arachnodactyly (spider-like fingers).
## **Correct Answer:** . Marfan syndrome