My posts refer to the distribution of HLA B27, not spondyloarthropathies, and according to latitude, not longitudinally around the north pole. And your last extract does refer to populations in the north with a high prevalence of HLA B27! You seem to be misreading me.
'Then you should say what you mean,' the March Hare went on. 'I do,' Alice hastily replied; 'at least - at least I mean what I say - that's the same thing , you know.' 'Not the same thing a bit!' said the Hatter.
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