Hi jroc,

I found this paper that you might find of interest since you've gone to the trouble of getting a genome scan.


The aim of the study was to investigate whether two ERAP1 nsSNPs non-synonomous Single Nulceotide Polymorphisms)- namely rs30187 and rs27044, influence the clinical characteristics of AS; in particular with respect to Age of Onset (arbitrarily set as <30 or >30) and whether or not the patient has Axial disease or Mixed disease (defined as axial AND peripheral manifestations)

Firstly, it is current consensus that the association of ERAP1 variants with AS is valid ONLY for HLA-B27 positive patients, but NOT for HLA-B27 negative ones.

The study found that there was association between the studied ERAP1 variants and the development of early onset AS.
So if you are HLAB-27+ but lack either of the two studied ERAP1 variants then you will probably develop late onset AS.

When restricting yourself to look at only AS sufferers who are HLA-B27+ early-onset patients, the study found that the rs30187 ERAP1 variant is associated with Axial-only group whilst the rs27044 ERAP1 variant is associated with the Mixed group (that axial AND peripheral symptoms).

Dx Oct 2006 B27+ undifferentiated spondlyarthropathy (uSpA) with mild sebhorrhoeic dermatitis and mild Inflammatory Bowel Disease (IBD) controlled by NSD since 2007.