1. Does the absence of a history of deafness in the parents and relatives mean that the child is not genetically deaf? Not necessarily. The recessive hereditary deafness, which accounts for 80% of hereditary deafness, can be caused by two parents who have normal hearing but carry a mutation in the deafness gene and pass the mutation on to their offspring. In this case, if a second child is considered, there is a 25% chance that the child will still have deafness. 2. If both parents or one parent is genetically diagnosed with deafness, what are the chances of having a child with deafness? Is there any way to prevent it? Since there are many genes related to hereditary deafness and various inheritance patterns, the possibility of having a child with deafness and the chance of having a child with deafness should be determined on a case-by-case basis based on genetic diagnosis. If a high risk of deafness is confirmed, amniocentesis and prenatal diagnosis of the deafness gene can be performed during pregnancy (about 17 weeks of gestation) to prevent it. 3. Is drug-related deafness not genetically related? People with several specific mitochondrial gene mutations are susceptible to aminoglycoside antibiotics, which can lead to drug-related deafness. These mitochondrial mutations can be passed on from mother to offspring. Through deafness genetic diagnosis, we can detect these mutations in the offspring or relatives of patients with drug-related deafness in advance and prevent the development of drug-related deafness by avoiding the use of aminoglycoside antibiotics. 4. Are there any risks in performing deafness genetic diagnosis? The test requires only 2 ml of peripheral blood (no fasting required) and our hospital guarantees complete confidentiality of the patient’s medical history, blood sample and test results. 5.What are the requirements and preparations for prenatal diagnosis of deafness in early pregnancy? Both spouses should complete the genetic diagnosis of deafness for each of them and their previous child before pregnancy, and based on the diagnosis results, first determine if prenatal diagnosis is necessary, and then perform prenatal diagnosis under the guidance of a physician. Important: There are many different types of deafness genes, and it usually takes more than 3 weeks to several months to determine the mutation carrier status of the parents and the previous child.