<prompt> A young, tall, thin, male with archnodactyly has ectopia lentis in both eyes. The most likely diagnosis isMarfans syndromeMarchesanis syndromeHomocystinuriaEhlers danlos syndrome  <response>: Answer is A Marfans syndrome: Arachnodactyly and ectopia lends dislocation of lens in tall thin male suggests a charachteristic diagnosis of Marfans syndrome. Marfan Syndrome : Review Marfans syndrome is a genetic disorder of the connective tissue of the body manifested principally by changes in the skeleton, eye and cardiovascular system. 