Question

A tall stature, long digits, long arm span, and subluxation of the lens is seen in which of the following defects?

• A. Fibrillin 1
• B. Collagen
• C.
• D.

Hint:

Marfan syndrome is caused by mutations in the fibrillin-1 gene, leading to features such as tall stature, arachnodactyly, and lens subluxation.

Answer 1

The Correct Option is A

The distinct features mentioned in the question—tall stature, long digits, long arm span, and subluxation of the lens—are characteristic of Marfan syndrome. This genetic disorder is known for affecting the body's connective tissue and is primarily caused by mutations in the FBN1 gene, which encodes the protein fibrillin-1.

Fibrillin-1 is a crucial component of connective tissue that contributes to the structural integrity of various body parts, especially in the skeleton, eyes, and cardiovascular system. The mutation in the fibrillin-1 protein disrupts normal connective tissue function, leading to the Marfan syndrome phenotype, including:

• Tall Stature: The individuals typically grow taller than average.
• Long Digits (Arachnodactyly): This term describes the elongated finger and toe shapes.
• Long Arm Span: The arm span of affected individuals often exceeds their height.
• Subluxation of the Lens: The lens of the eye is frequently displaced due to weakened connective tissue.

Given these facts, the correct answer to the question is that defects in Fibrillin 1 lead to the observed symptoms in the question prompt.