1.An AnaIysis of Newborn Hearing Concurrent Genetic Screening ResuIts
Zhenan LI ; Shuzhen LIANG ; Fengci YU ; Tangjing HE ; Yun LIU ; Qingquan HE
Journal of Audiology and Speech Pathology 2014;(6):585-588
Objective To analyze clinical results of newborn hearing concurrent genetic screening and to ex-plore the significance of genetic test and potential correlations between the genotype and clinical phenotype.Methods Newborns in Foshan born during May,2012 and September,2013 were recruited.Two-step hearing screening was carried out by using AABR (automated auditory brainstem response).Blood samples were collected with a standard protocol for testing hot-spot mutations of common deafness-susceptibility genes.ResuIts A total of 10 238 newborns,including 9 295 rooming-in infants and 943 NICU infants,received hearing screening and 99.16%of passed the initial screening.The passing rates of rooming-in and NICU infants were significantly different (χ2 =99.1,P<0.001),but the difference was not significant in the secondary screening (χ2 =0.26,P=0.61).Three hundred and fifteen out of 10 238 (3.08%)newborns who underwent genetic testing were found to have one or two allele mutations of deafness-susceptibility genes,and the positive rate of genetic screening was significantly higher than the referring rate of initial hearing screening (χ2 =123.9,P<0.001).Newborns with gene mutations had high-er referring rate of hearing screening than the general population (χ2 =72.4,P<0.001).GJB2 c.235delC heterozygous mutation frequency was 1.61% (165/10 238),while the homozygous mutation frequency was 0.04% (4/10 238);c.299 300delAT heterozygous mutation frequency was 0.20% (20/10 238);c.176 191del16 heterozygous mutation frequency was 0.06% (6/10 238);no c.35delG mutation was detected.SLC26A4 c.919-2A>G heterozygous mu-tation frequency was 0.80% (82/10 238)and the homozygous mutation frequency was 0.03% (3/10 238);c.2168A>G heterozygous mutation frequency was 0.12% (12/10 238).MTRNR1 1555A>G heteroplasmic mutation fre-quency was 0.04% (4/10 238)while the homoplasmic mutation frequency was 0.18% (18/10 238).1494C>T ho-moplasmic mutation frequency was 0.01% (1/10 238).GJB2 c.235delC and SLC26A4 c.919 -2A>G mutations were found to be the most recurrent mutations in participants,and finally eight infants aged 6 days to 25 months di-agnosed with moderate to very severe sensorineural hearing loss were correlated with these two mutations.ConcIu-sion Genetic screening is a potent strategy to complement the conventional hearing screening since it is helpful for determining high risk individuals and early discovering possible late-onset hearing loss.