In HLA-B27-positive individuals who have relatives with the disease, the risk of developing ankylosing spondylitis is 12% (six times greater than for those whose relatives do not have ankylosing spondylitis).
HLA-B27-positiivsed isikud, kellel on sugulased haigus, risk haigestuda anküloseeriv spondüliit on 12% (kuus korda suurem kui nende jaoks, kelle sugulased pole anküloseeriva spondüliidiga).