According to a story from Angioedema News, a recent study discusses a genetic procedure called allelic discrimination as a method for diagnosing hereditary angioedema. The study concluded that this method can be done more quickly and more cheaply than other processes such as Sanger sequencing. This new approach is specifically beneficial for those patients who have mutations affecting the F12 gene, which is often more difficult to detect and diagnose.
About Hereditary Angioedema (HAE)
Hereditary angioedema is a genetic disorder which is characterized by chronic episodes of swelling that can affect multiple areas of the body. The condition is caused by mutations affecting the SERPING1 gene. Swelling attacks generally occur every two weeks or so; they can usually last for several days. Swelling may affect the limbs, digestive tract, face, and airway, with blockage of the airway being the most dangerous complication. Vomiting and abdominal pain may accompany attacks as well if the digestive tract is involved. Treatment involves reducing the likelihood for attacks to appear and preventing them from worsening when they do. Hereditary angioedema is typically only life-threatening if left untreated. Prevalence of the condition is estimated to be around one in 10,000 to one in 50,000, at least in the US and Canada. To learn more about hereditary angioedema, click here.
Most often, the disorder is linked to mutations affecting the SERPING1 gene, but more rarely, the F12 gene may be affected. This mutation was more recently discovered and is far less commonly encountered. F12 mutated patients are more likely to experience diagnostic delays, putting them at greater risk.
About The Study
In the study, allelic discrimination was tested on 184 people that had a family history of the condition. Most participants were women (73.9 percent) and varied in age from two months to 91 years. This same sample was also tested using Sanger sequencing. Allelic discrimination detected F12 mutations in 96 percent of the patients, which was further confirmed by the Sanger sequencing.
However, the researchers calculated that allelic discrimination cost $91.08 and six hours for a single case compared to $496.69 and 38.5 hours using Sanger sequencing. Even if samples were processed in bulk, Sanger sequencing was still more costly and took considerably longer. The researchers recommend that patients that present with symptoms but don’t have the most common SERPING1 mutation should undergo allelic discrimination as the first-line diagnostic method.
Check out the original study here.