Is gastric cancer hereditary?

If we divide these regions into developed and developing regions, we can see that there are fewer cases in developed countries and more in developing regions. my country is a country with a high incidence of gastric cancer. Before the 1980s, gastric cancer was always the first in cancer incidence, but in recent years, the incidence of gastric cancer has declined, especially in some large cities. Is there a genetic tendency for gastric cancer?

In the past thirty years, a comparative study of areas with high and low incidence of gastric cancer has found many factors related to the onset of gastric cancer. In some areas with high incidence of gastric cancer, it can be found that some families have gastric cancer for several generations. Some people call this phenomenon family clustering or family concentration.

The most famous family with stomach cancer is the Napoleon family. Everyone knows Napoleon. Napoleon's father, his sister, and Napoleon himself all had stomach cancer. It is said that Napoleon's grandfather and some of his other brothers and sisters may also have stomach cancer.

There have been literature reports that show that people with a family history of gastric cancer have several times higher chances of developing gastric cancer than those without a family history of gastric cancer.

Is there a hereditary tendency for gastric cancer? Some scholars once believed that the clustering of gastric cancer in a family might be related to living together, because they live in the same environment and have the same eating habits. But later it was discovered that couples living in the same environment rarely develop gastric cancer together, while parents and children with the same blood relationship can also develop gastric cancer even if they live in different places.