Celiac disease
From SNPedia
Celiac disease, also known as gluten intolerance, is an autoimmune disorder of genetically predisposed individuals, provoked by gluten proteins in wheat and related foods. Wikipedia
SNPs associated with celiac disease:
- HLA-DQ
- rs2187668 (HLA-DQA1)
- In a 2003 survey of European studies, more than 85% of celiac patients carry the same HLA-DQ heterodimer DQA1*05 DQB1*02 (aka DQ2.5) encoded in cis or in trans [PMID 12209133]; almost all the remaining cases carry either the DQA1*05 or the DQB1*02 part of the DQ heterodimer, or DRB1*04-DQ8. [PMID 14571266]
- rs2187668(A) is a tag SNP for DQ2.5 [PMID 18509540]
- rs2395182, rs7775228, and rs4713586 create a haplotype tag for DQ2.2; see gs221 [PMID 18509540]
- rs7454108 tags the HLA-DQ8 haplotype
- A large study of 2,000+ celiac disease patients found SNP associations in 7 chromosomal regions. Six of these regions harbor genes controlling immune responses, including CCR3, IL12A, IL18RAP, RGS1, SH2B3 (rs3184504), and TAGAP. [PMID 18311140]
- near CCR3
- rs6441961 (risk allele T) [PMID 19542083] [PMID 19648290]
- IL18RAP
- rs917997 (possibly a weak association) [PMID 19542083]
- near the IL21 gene
- rs13119723 (risk allele G) [PMID 17558408] [PMID 18418394]
- rs6822844 (higher risk allele is G, since T allele is reported to reduce risk) [PMID 17558408] [PMID 18418394]
- near the LPP gene
- near ITGA4 [PMID 19648293]
Although the HLA-DQ2 and DQ8 haplotypes are associated with gluten intolerance, as a 2010 blog post indicates, the frequency of these haplotypes (20-30%) is much higher than the frequency of celiac disease (~1%), so perhaps the primary value of SNP testing in this context is to rule out the likelihood of gluten intolerance. In other words, if you are among the 70-80% of individuals who do not carry HLA-DQ2 and/or DQ8 haplotypes, you are quite likely (> 95%) to tolerate gluten and to not be at risk for celiac disease.
