According to a story from Genome Web, a team of researchers from across the country have concluded an in-depth genetic analysis focused on the origins of Hirschsprung’s disease, a rare disease that is distinguished by the absence of nerves in certain parts of the intestine. What they found revealed that risk variants for the disease were substantially more complex than expected.
About Hirschsprung’s Disease
Hirschsprung’s disease is a genetic disorder which is characterized by the absence of certain nerves in part of the intestine. This can cause frequent constipation and other symptoms to appear. Males are more commonly affected than females. The condition may appear on its own or alongside other genetic conditions, such as Down syndrome. The condition can be heritable within a family or may be the result of a new mutation; the most commonly affected gene is the RET gene. Less commonly the NRG1 or NRG3 gene is affected. The cause is not clear in all cases. Symptoms appear within the first few months of life, and usually include constipation, slow growth, vomiting, diarrhea, and abdominal pain. It can also cause more severe complications like intestinal perforation, megacolon, or bowel obstruction. Hirschsprung’s disease is most commonly treated with surgical removal of the affected portion of the intestine. To learn more about Hirschsprung’s disease, click here.
The type of genetic variants that were linked to the disease varied broadly, and included rare coding variants, copy number variants, more common polymorphisms, single nucleotide variants, and non-coding variants. The research involved sequencing samples from 190 patients with Hirschsprung’s disease. These results were compared to data from 627 healthy controls. The data could eventually be used in the future to help classify different cases and help predict disease course. The scientists also hoped that the results could help explain disparities in outcomes following surgical intervention.
While there were several genetic variants that were decisively more common in Hirschsprung’s disease patients compared to the controls, one gene that seemed to particularly affected was the RET gene. 72 percent of patients had changes that affected this gene, compared to less than half of the control group.
The findings were originally published here, in the New England Journal of Medicine.