Gene changes linked to stomach cancer:
US researchers have identified genetic changes in people with a hereditary form of stomach cancer. People who inherit a CDH1 gene mutation have a greatly increased risk of developing hereditary diffuse gastric cancer (HDGC), the Vancouver team has confirmed. Their findings, published in the Journal of the American Association, suggest that a faulty CDH1 gene is responsible for the disease in up to 50 per cent of affected families.
While rates of stomach cancer overall have dropped dramatically in recent years, thanks largely to better quality food, the number of people affected by the inherited form of the disease has remained unchanged. The average age for someone with HDGC to be diagnosed with gastric cancer is 38, whereas ‘sporadic’ gastric cancers tend to occur in individuals older than 60. Women with HDGC also have an increased risk of lobular breast cancer, and some people may also have some increased risk of colorectal (bowel) cancer.
Researchers have known for several years that mutations in the CDH1 gene can cause HDGC. In the latest study, the scientists looked at DNA samples from 38 affected families, and found CDH1 mutations in 15 of them. The team also discovered that one particular CDH1 mutation is shared by four families originating from Newfoundland, suggesting they all inherited HDGC from a common ancestor.
‘Our results confirm that between 30 per cent and 40 per cent of families with a positive family history of gastric cancer and more than 50 per cent of families with two diffuse gastric cancer cases diagnosed prior to age 50 years will carry germline mutations in the CDH1 gene’, the authors write. ‘The identification of CDH1 mutations offers the opportunity of cancer risk-reduction strategies for unaffected at-risk individuals’, they conclude.
Sources:
Genetic Mutations Identified For Type Of Gastric Cancer: Science Daily: 4 June 2007
Clinical Implications of Founder and Recurrent CDH1 Mutations in Hereditary Diffuse Gastric Cancer: JAMA: 3 June 2007 (EOP)