Deaf children can be born to couples with normal hearing. 80% of deaf children in China have parents with normal hearing. I. Dangers and Causes of Deafness Every year, 30,000 congenitally deaf children are born in China, and with the addition of acquired deafness such as late-onset deafness and drug-related deafness, 60,000-80,000 new deaf children will be born every year. Hearing disability accounts for 33% of the total number of people with disabilities in China, which is the highest. The only way to improve hearing is to wear hearing aids or cochlear implants, which require long-term rehabilitation after surgery. Even after the surgery and rehabilitation, some people still do not recover their hearing well, and even if they do, their hearing is still different from normal hearing. Before the age of 3 is a critical period for babies to develop their speech and language skills, missing this period can result in babies without speech. An important prerequisite for the formation of language skills is good hearing. Babies who lose their hearing cannot learn to speak because they cannot receive external language signals and eventually become “mute”. Genetic factors are the main cause of deafness, and most of the genetic deafness is recessive, that is, if parents have normal hearing, but both carry the same deafness gene mutation, there is a 25% chance of having a deaf child. More than 5% of normal people carry the deafness gene mutation, which is the highest rate of carriage of any single-gene genetic disorder and therefore results in the highest incidence of inherited deafness among single-gene genetic disorders. Parents often ask their doctors, “We have normal hearing and no deaf patients in our family, why is our child deaf? This is the reason. In China, there are 27.8 million people with hearing impairment, and about 78 million people are carriers of deafness mutation. The high carriage rate of deafness mutation causes the high incidence of deaf children. Prevention of deafness Prenatal deafness genetic testing is the first line of defense to prevent deafness, which can determine the hearing condition of the fetus before birth and prevent the birth of a deaf child as much as possible. In addition, genetic testing for deafness can detect later-onset deafness and drug-related deafness. If prenatal genetic testing for deafness is missed, genetic testing can be performed on the newborn, which is the second line of defense to prevent later-onset deafness and drug-related deafness by providing life coaching and avoiding the use of ototoxic drugs to slow or avoid the onset of later-onset deafness. The deafness gene chip can detect 80% of genetic deafness mutations. Prenatal screening requires only a blood test, and testing of the fetus is only necessary if both parents carry the same genetic mutation.