Skip Navigation


Rheumatology Advance Access originally published online on September 9, 2009
Rheumatology 2009 48(11):1424-1428; doi:10.1093/rheumatology/kep243
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
48/11/1424    most recent
kep243v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Karason, A.
Right arrow Articles by Gudbjornsson, B.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Karason, A.
Right arrow Articles by Gudbjornsson, B.
Related Collections
Right arrow Spondylarthropathies
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2009. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

A strong heritability of psoriatic arthritis over four generations—the Reykjavik Psoriatic Arthritis Study

Ari Karason1, Thorvardur Jon Love2,3 and Bjorn Gudbjornsson2,4

1deCODE Genetics, 2Centre for Rheumatology Research, Landspitali – University Hospital, Reykjavik, Iceland, 3Brigham and Women's Hospital, Harvard Medical School, Boston, USA and 4Faculty of Medicine, University of Iceland, Reykjavik, Iceland.

Correspondence to: Björn Gudbjörnsson, Centre for Rheumatology Research, Landspitali – University Hospital, v/Hringbraut, 101 - Reykjavik, Iceland. E-mail: bjorngu{at}landspitali.is


  Abstract

Objective. We have studied the prevalence of PsA in Reykjavik, Iceland, in a population-based cohort, and using the Icelandic genealogy database we have estimated the risk ratio (RR) spanning five generations.

Methods. The national identification numbers of all 220 living Icelanders in Reykjavik known to have PsA were linked with the genealogy database. RRs for developing PsA were estimated in first-degree relatives (FDRs) to fifth-degree relatives of PsA cases. The kinship coefficient (KC) for PsA was also calculated. The control populations were 1000 and 10 000 sets of matched Icelandic subjects for each proband, respectively.

Results. FDRs to fourth-degree relatives of patients with PsA had RRs of 39, 12, 3.6 and 2.3, respectively (all P-values < 0.0001), reflecting a strong genetic component, whereas the fifth-degree relatives had an RR of 1.2 (P = 0.236). KCs of 5.0, 3.4, 1.7, 1.3, 1.0, 0.8 and 0.7 were observed for the first seven excluded meioses (all P-values < 0.0001), confirming the familial risk.

Conclusions. Patients with PsA in Reykjavik, Iceland, are significantly more related to each other than to randomly sampled control subjects. This is in agreement with previous reports, but the present study examines the inheritance in more distantly related individuals. These findings indicate that in addition to a strong and complex genetic component in PsA, there is an important environmental contribution.

KEY WORDS: Genealogy database, Heritability, Psoriatic arthritis, Familial, Genetic

Submitted 24 April 2009; revised version accepted 13 July 2009.
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.