PTPN22 polymorphisms may indicate a role for this gene in atopic dermatitis in West Highland white terriers.
BACKGROUND
Canine atopic dermatitis is an allergic inflammatory skin disease common in West Highland white terriers. A genome-wide association study for atopic dermatitis in a population of West Highland white terriers identified a 1.3 Mb area of association on CFA17 containing canine protein tyrosine phosphatase non-receptor type 22 (lymphoid) PTPN22. This gene is a potential candidate gene for canine atopic dermatitis as it encodes a lymphoid-specific signalling mediator that regulates T-cell and possibly B-cell activity.


RESULTS
Sequencing of PTPN22 in three atopic and three non-atopic West Highland white terriers identified 18 polymorphisms, including five genetic variants with a bioinformatically predicted functional effect. An intronic polymorphic repeat sequence variant was excluded as the cause of the genome-wide association study peak signal, by large-scale genotyping in 72 West Highland white terriers (gene-dropping simulation method, P = 0.01).


CONCLUSIONS
This study identified 18 genetic variants in PTPN22 that might be associated with atopic dermatitis in West Highland white terriers. This preliminary data may direct further study on the role of PTPN22 in this disease. Large scale genotyping and complementary genomic and proteomic assays would be required to assess this possibility.
Centre for Companion Animal Health, School of Veterinary Science, The University of Queensland, St Lucia, Queensland, 4069, Australia. c.oleary@uq.edu.au.
Joana Barros
JB
Roque
Caroline A
CA
O'Leary
Myat
M
Kyaw-Tanner
David L
DL
Duffy
Puya
P
Gharahkhani
Linda
L
Vogelnest
Kenneth
K
Mason
Michael
M
Shipstone