This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
A 35 year old tall male from New Jersy has Marfan syndrome, an autosomal dominant disorder with features of subluxated lens of the eye, mitral valve prolapsed. The defect lies in: 
Select and explain. 
A. Gene on chromosome 15 encoding fibrillin, B. Gene on chromosome 16 encoding fibrillin, C. Gene on chromosome 17 encoding fibrillin, D. Gene on chromosome 18 encoding fibrillin
A: Gene on chromosome 15 encoding fibrillin
Answer: A: Gene on chromosome 15 encoding fibrillin 
Explanation: Gene on chromosome 15 encoding fibrillin