GENE INCREASES RISK OF REFRACTORY CD

The MYO9B gene is a strong risk factor for developing refractory celiac disease, finds a report in the latest issue of Clinical Gastroenterology and Hepatology.

Celiac disease is associated with HLA-DQ2 and HLA-DQ8, and has been linked to genetic variants in the MYO9B gene on chromosome 19. HLA-DQ2 homozygosity is associated with complications of celiac disease such as refractory celiac disease type II, and enteropathy-associated T-cell lymphoma. Doctors from the Netherlands investigated whether MYO9B also predisposes to refractory celiac disease type II and enteropathy-associated T-cell lymphoma. The team performed genotyping of MYO9B and molecular HLA-DQ2 typing on 62 refractory celiac disease type II and enteropathy-associated T-cell lymphoma patients. The researchers also performed the genotyping and molecular typing on 421 uncomplicated celiac disease patients, and 1,624 controls.

The researchers found that a single nucleotide polymorphism in MYO9B showed a significantly different allele distribution in refractory celiac disease type II and enteropathy-associated T-cell lymphoma patients compared with controls. The team observed that the rs7259292 T allele was significantly more frequent in refractory celiac disease type II and enteropathy-associated T-cell lymphoma patients compared with celiac disease patients. The researchers noted that the frequency of the haplotype carrying the T allele of this single nucleotide polymorphism occurred in 11 percent in refractory celiac disease type II and enteropathy-associated T-cell lymphoma patients. The team found the frequency of this polymorphism occurred in 2 percent of controls, and 3 percent with celiac disease patients. Both MYO9B rs7259292, and HLA-DQ2 homozygosity increase the risk for refractory celiac disease type II and enteropathy-associated T-cell lymphoma to a similar extent when compared with uncomplicated celiac disease patients. However, there was no evidence for any interaction between these two risk factors.