Oddly, having the gene alone (without other signs) means that you are statistically likely not to have AS.
This is a scientific impossibility, as-stated. Ebringer has claimed that, with the antigen, the chances for developing Crohn's Disease are reduced considerably. Or, if You mean that, with the progression of age after perhaps frequency peak 19-23, the potential becomes less likely a person with the antigen will develop AS...well that should also be disputed!
It is worth noting that FIFTY percent
of HLA B27+ males (in Holland) at some time during their lives seek medical attention for severe "back pain." This compares with FIVE percent
in the verified HLA B27- population. AS is transient and variable and often causes no pain even while severe damage progresses.
In re Carol Sinclair: She cannot get an "official" AS diagnosis because she has refused to allow her SIJs to fuse; she does not need the diagnosis anyway, but it would be helpful--and is of considerable value--to know that she is HLA B27+, as was (probably) her hunched-over father and nephews, who also have enough knowledge and sense to properly treat their AS before 'benign neglect' results in obvious easy diagnosis.
The condition of "PRE-AS" should be recognized in the near future, and by then the medical guilds might be capable of preventing the characteristic fusion (permanent damage). The antigen makes PRE-AS much easier to diagnose, but the challenge is to the patient now to prevent AS (99% of rheumatologists are helpless in this quest).