Related Experiment Video
Updated: Dec 28, 2025

Candidate Gene Testing in Clinical Cohort Studies with Multiplexed Genotyping and Mass Spectrometry
Published on: June 21, 2018
Genetic Analysis of Ulcerative Colitis in Japanese Individuals Using Population-specific SNP Array
Daisuke Okamoto1, Yosuke Kawai2, Yoichi Kakuta1
1Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan.
Background:
To clarify the genetic background of ulcerative colitis (UC) in the Japanese population, we conducted a genome-wide association study (GWAS) using a population-specific single nucleotide polymorphism (SNP) array.
Methods:
We performed a GWAS and replication study including 1676 UC patients and 2381 healthy controls. The probability of colectomy was compared between genotypes of rs117506082, the top hit SNP at HLA loci, by the Kaplan-Meier method. We studied serum expression of miR-622, a newly identified candidate gene, from 32 UC patients and 8 healthy controls by quantitative reverse-transcription polymerase chain reaction.
Results:
In the GWAS, only the HLA loci showed genome-wide significant associations with UC (rs117506082, P = 6.69E-28). Seven nominally significant regions included 2 known loci, IL23R (rs76418789, P = 6.29E-7) and IRF8 (rs16940202, P = 1.03E-6), and 5 novel loci: MIR622 (rs9560575, P = 8.23E-7), 14q31 (rs117618617, P = 1.53E-6), KAT6B (rs12260609, P = 1.81E-6), PAX3-CCDC140-SGPP2 (rs7589797, P = 2.87E-6), and KCNA2 (rs118020656, P = 4.01E-6). Combined analysis revealed that IL23R p.G149R (rs76418789, P = 9.03E-11; odds ratio [OR], 0.51) had genome-wide significant association with UC. Patients with GG genotype of rs117506082 had a significantly lower probability of total colectomy than those with the GA+AA genotype (P = 1.72E-2). Serum expression of miR-622 in patients with inactive UC tended to be higher than in healthy controls and patients with active UC (inactive UC vs healthy controls, P = 3.03E-02; inactive UC vs active UC, P = 6.44E-02).
Conclusions:
IL23R p.G149R is a susceptibility locus for UC in Japanese individuals. The GG genotype of rs117506082 at HLA loci may predict a better clinical course.
More Related Videos
05:58Digital Polymerase Chain Reaction Assay for the Genetic Variation in a Sporadic Familial Adenomatous Polyposis Patient Using the Chip-in-a-tube Format
Published on: August 20, 2018
06:21Author Spotlight: Genetic Profiling for Fluorouracil Response in Gastric Cancer
Published on: May 10, 2024
Related Concept Videos
Genome-wide Association Studies-GWAS
GWAS does not require the identification of the target gene involved in...
Single Nucleotide Polymorphisms-SNPs
Comparing Copy Number Variations and SNPs
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...