For psoriasis we know that there is a certain amount of heredity, that is, one member of the family has psoriasis, other members may have a susceptibility gene for psoriasis, so how is the probability of heredity of psoriasis? Psoriasis is a common chronic skin disease characterized by the repeated appearance of multiple layers of silvery-white dry scales on red patches. It is called white mange in ancient Chinese medicine, and it is also called pine skin ringworm in ancient medical texts. Psoriasis, commonly known as psoriasis in Western medicine, is characterized by the appearance of papules of varying sizes, erythematous plaques covered with silvery-white scales, and clearly defined borders, usually on the scalp, extensor surfaces of the extremities and back. It is more common in men than in women. It tends to recur or worsen during spring and winter, and remits more often in summer and fall. The probability of heredity of psoriasis 1, the incidence of the patient’s relatives will have a certain relationship with their relatives, the greater their incidence the higher his heredity. The incidence rate of a patient’s relatives increases or decreases with the proximity of the first diseased person to that relative, and the closer the relationship the higher the incidence rate. 2, the risk of psoriasis has a certain relationship with heredity, generally the greater the heredity, the higher the probability of heredity of psoriasis in close relatives, so for patients should pay more attention. 3, When there is a gender difference in its prevalence, the risk rate of disease is higher for relatives of the lesser sex. 4, generally patients aggravated by the disease more people, then the family is likely to him. 5, the offspring of inbred marriages have a greater chance of disease than those who are not inbred. 6, for the more serious the disease, and the more serious the disease the higher the risk of disease in the family.