This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetic and genetic disorders, Subject name: Pediatrics
Which of the following is a feature of Marfan&;s syndrome? 
Select and explain. 
A. Pulmonary hypeension, B. Mental retardation, C. Emphysema, D. Subluxuation of lens
D: Subluxuation of lens
Answer: D: Subluxuation of lens 
Explanation: Subluxuation of lens is associated with Marfan&;s syndrome. Features of Marfan&;s syndrome Mitral valve prolapse Myopia due to upward dislocation of lens (bilateral ectopic lentis) Aoic root dilatation, Aoic regurgitation Retinal detachment Fibrillin 1 gene defect: Reduced fibrillin 1 production causing joint laxity Fifteen (chromosome 15 is invloved) Flat feet Arachnodactyly, Astigmatism, Air in lungs (Pneumothorax) Near Sightedness Subluxuation of lens, Scoliosis, Speech disorders, Sleep apnea Ref: Nelson textbook of pediatrics 21st edition Pgno: 3741