<prompt> Keratoconus is associated with all exceptDowns syndromeEhlersDanlos syndromeMarfans syndromeUshers syndrome  <response>: Systemic conditions associated with keratoconus are a marfan syndrome, osteogenesis- imperfecta, EDS, Downs syndrome, MVP, atophy asthma, eczema, atopic keratoconjunctivitis, hay fever. 