Crohn's disease is described as a multigenic disorder. The presence of certain alleles may increase the risk that a patient will develop Crohn's disease.
|
Allele |
Code |
Criteria for Risk (Weersma et al) |
|
autophagy-related 16-like 1 |
ATG16L1 |
rs2241880*G |
|
Drosophila discs large homologue 5 |
DLG5 |
rs2289310*C |
|
inflammatory bowel disease 5 |
IBD5 |
rs2522027*C |
|
interleukin 23 receptor |
IL23R |
homozygous for rs11209026*G |
|
nucleoside-binding and oligomerisation domain 2 |
NOD2 |
polymorphisms in one or more of: R702W, G908R, 3020insC |
|
Allele |
Chromosome Location |
|
ATG16L1 |
2q37.1 |
|
DLG5 |
10q23 |
|
IBD5 |
5q31-q33 |
|
IL23R |
1p31.3 |
|
NOD2 |
16q21 |
where:
• IBD5 includes SLC22A4 and SLC22A5 (solute carrier family 22 members 4 and 5)
number of alleles =
= (presence of 1 or more NOD1 risk alleles) + (number of ATG16L1 alleles) + (number of DLG5 alleles) + (number of IBD5 alleles) + (homozygous for IL23R)
|
Number of Alleles Present |
Odds Ratio for Crohn's Disease |
|
0 or 1 |
1 |
|
2 |
1.8 |
|
3 |
2.7 |
|
4 |
4.3 |
|
5 |
5.9 |
|
6 |
7.6 |
|
7 |
25.6 |
|
8 or 9 |
NA |
where:
• According to the text on page 393 of Weersma et al the maximum number of risk alleles is 9, but my maximum count is 8. One way to a higher number is to count the number of alleles in IL23R.
Specialty: Gastroenterology
