Thumb with only soft tissue and no bone is an autosomal dominant disorder, characterized by cardiovascular and skeletal malformations as the main clinical manifestations. Chromosomal disorders are not uncommon in the population, and there are more than 300 known human genetic disorders caused by chromosomal abnormalities, all of which have some numerical or structural abnormalities of the cell chromosomes. The diagnosis of chromosomal disorders can be accomplished by microscopic analysis of chromosomes. The medical technicians who perform this work are professionally trained and therefore have some experience. They have no difficulty in distinguishing a complete karyotype under the microscope into 7 groups: A, B, C, D, E, F, G. Each karyotype is carefully checked according to the structural characteristics and number of chromosomes. If there is any structural abnormality of any chromosome, such as translocation, deletion, duplication, inversion, etc., or if there is a change in the number of chromosomes, such as an extra chromosome or a missing chromosome, it can be detected immediately and thus be diagnosed whether it is a chromosomal disorder. There are dominant and recessive autosomal genetic disorders, and the following principles must be followed when a mother of a child with this disorder becomes pregnant again: 1. Autosomal dominant disorders If the affected child has a sick parent, i.e. one of the parents is a patient, then there is a 1/2 chance that each child will develop the disease and the risk of recurrence is too high, so it is best not to have another child in this case. If the child has no offspring with the disease, i.e., the parents are normal and there is no history of genetic disease after a family survey. In this case, the appearance of the affected child is mostly the result of mutation, and generally the mutation rate is low, so the second child can be born. 2. Autosomal recessive disorders The parents are normal in appearance, but they are both carriers of the disease causing gene, so there is a 1/4 chance for each child to develop the disease and the risk of recurrence is high. For diseases that can be prevented and treated in the neonatal period, such as phenylketonuria and galactosemia, the second child is allowed in areas where conditions exist (only when the first child has already caused irreversible mental retardation and other pathological damage), but laboratory tests must be done after birth, and if the child is affected, he or she must be treated promptly with lifelong medication or a controlled diet. In general, most of the chromosomal abnormalities carriers belong to translocation carriers, the physical and mental abilities of this patient are not different from normal people, but they may be found to be chromosomal translocation carriers from the following cases: birth of multiple congenital malformations (with unbalanced translocations); women with a history of habitual abortion, the cause of which is not determined by other methods (non-chromosomal tests), 30%-40% of congenital stupidity is caused by In 30%-40% of cases, congenital dysgenesis is caused by a translocation of chromosome 21. The risk of having a child with an unbalanced chromosome translocation varies according to the type of translocation and whether the carrier is the mother or the father, but clinically there are more balanced than unbalanced translocations.