Typified by incomplete penetrance Typified by low penetrance 2023-01-26T17:19:09Z Description of conditions in which only a low proportion of individuals with a given genotype exhibit the disease regardless of age assuming a full lifespan of 80 years. There is no commonly accepted definition for low penetrance, but we suggest that this term be applied if at least some but less than 20 percent of carriers would manifest the disease with a full lifespan.