Macrodactyly is a congenital malformation characterized by an increase in the size of the fingers or toes due to abnormal nerve growth and has a low incidence of about 0.9% among congenital malformations of the extremities. Macrodystrophy usually occurs immediately after birth, while the other fingers or toes are normal. Significant enlargement of one or several fingers may be seen, but not all fingers are necessarily involved. Cases of limited hypertrophy have been reported in which the damage involves only the distal ends of the fingers. Prevention of giant fingers (toe) syndrome should pay attention to the following points: 1, the implementation of eugenics protection method Anyone who can certainly or has a high probability of causing congenital abnormal diseases in their offspring should try to avoid having children. These diseases include idiocy, congenital stupidity, hereditary psychosis, significant hereditary somatic disorders such as chorea and myasthenia gravis, albinism, etc. 2, avoid consanguineous marriage consanguineous marriage will increase the incidence of genetic diseases, which has been confirmed in medical statistics. Such as “hepatomegaly” patients. The incidence of non-consanguineous marriage offspring is 1 / 4 million, while the incidence of cousin marriage offspring is increased to 1/64. another example is the children born of consanguineous marriage poor intelligence than non-consanguineous marriage 3.8 times more, so our marriage law prohibits consanguineous marriage. 3, to avoid senior childbirth The birth age of both spouses should not exceed 35 years old. 4, genetic counseling, especially those with a history of birth deformities.