Is longevity determined by genetics?

Title: Is longevity determined by genetics?

Article Snip: "The duration of human life (longevity) is influenced by genetics, the environment, and lifestyle. ...Now people in the United States live about 80 years on average, but some individuals survive for much longer. Scientists are studying people in their nineties (called nonagenarians) and hundreds (called centenarians, including semi-supercentenarians of ages 105-109 years and supercentenarians, ages 110+) to determine what contributes to their long lives. They have found...The study of longevity genes is a developing science. It is estimated that about 25 percent of the variation in human life span is determined by genetics, but which genes, and how they contribute to longevity, are not well understood. A few of the common variations (called polymorphisms) associated with long life spans are found in the APOE, FOXO3, and CETP genes"

Reference: medlineplus.gov