Combined Hearing and Genetic Screening in 30835 Neonates

ZHANG Wanxia; SUN Huihong; MA Lixia; LI Yichen

doi:10.3969/j.issn.1672-2922.2016.06.013

Abstract：Objective To report data of combined newborn hearing and genetic screening in Beijing and its potential values. Methods Newborns born between July 2013 and June 2015 were included in the study. After obtaining the informed consent, hearing screening was conducted within 48 hours after birth. At the same time, heel blood collection was done for genetic screening for nine hot spot mutations in four common deafness genes. Those failing to pass the initial hearing screen-ing received the second round screening at 42 days after birth in the maternity hospital. Those failing the combined screen-ing were referred to one of the six state designated diagnosis and treatment centers for pediatric hearing impairment in 3 months. The centers provided diagnostic hearing testing and genetic counseling. Data from combined screening were col-lected and analyzed. Results A total of 30,835 newborns (97.6%of the newborns in the study duration) received combined hearing/genetic screening, showing successful outreach efforts well received by the community. The rate of hearing screen-ing failure was 1.51%and that of genetic screening failure was 4.73%. The rate of hearing screening failure among the new-borns who failed the genetic screening (3.8%) was higher than that among those passing the genetic screening (1.4%) (P<0.001), suggesting that failing either screening modality could represent increased risk of failing the other screening modali-ty. Among the 1,457 newborns who failed the genetic screening, GJB2 gene mutations were the most commonly seen (55.4%), followed by SLC26A4 gene mutations (34.3%). There were 74 cases of mitochondrial 12s rRNA gene mutations. Five newborns were found to have homozygous or compound heterozygous mutations and hearing loss was confirmed in four of them. Heterozygous mutations were found in 1,452 newborns, and14 of them were diagnosed with hearing loss. Conclusions Combined hearing/genetic screening is feasible and easy to be adopted in clinical practice. The hearing and ge-netic screenings are complimentary to each other. The combined screening is the most effective screening modality available today.