Marfan's syndrome is an inherited connective tissue disorder that is caused by a mutation in a gene that codes for an extracellular matrix protein-fibrillin-1 (FBN1). The FBN1 locus is on the long arm of chromosome 15. It is a clinical diagnosis based on skeletal, cardiovascular, and ocular manifestations. Skeletal manifestations: • Overgrowth of long bones (dolichostenomelia) with an arm span to height ratio of more than 1.05 • Pectus carinatum or pectus excavatum • Long and slender fingers (arachnodactyly), contracture of fingers (camptodactyly) • Malar hypoplasia • Joint laxity Cardiovascular manifestations: • Thickened atrioventricular valves, valvular prolapse (mitral regurgitation) • Aortic valve dysfunction due to aortic root aneurysm • Aortic dissection and rupture due to cystic medial necrosis of the aorta Ocular manifestations: • ectopia lentis • myopia • flat cornea