OBJECTIVE: To detect common pathogenic variants associated with congenital deafness among neonates from Huizhou and surrounding areas and discuss its implications. METHODS: Thirteen hot-spot mutations in four most common pathogenic genes were screened among 20 934 neonates from March 2017 to December 2019. RESULTS: In total 760 neonates were found to carry common pathogenic variants (3.63%). Sixty two neonates have carried homozygous/compound heterozygous variants or homoplasmy/heteroplasmy mutations of mtDNA (0.29%). Further analysis of five abnormal cases revealed that 3 of them have carried compound heterozygous mutations of GJB2 gene, and 2 were due to compound heterozygous variants of the CDH23 gene. CONCLUSION Genetic testing has a great clinical significance for the prevention and reduction of congenital hearing loss, but the scope needs to be updated and redefined by removing mutation sites with a very low rate, adding new significant sites, and improvement of the technical strategies.
Connexin 26 ; Connexins/genetics* ; DNA Mutational Analysis ; Deafness/genetics* ; Genetic Testing ; Hearing Loss/genetics* ; Humans ; Infant, Newborn ; Mutation ; Neonatal Screening

Objective:To investigate the effects of ectodysplasin-A1 (EDA1) on the proliferation and cell cycle of ameloblast-like epithelial cells (LS8 cells).Methods:Wild EDA1 plasmid pCR3-Flag-EDA1-W (wild group), syndrome mutant EDA1 plasmid pCR3-Flag-EDA1-H252L (mutant group) and empty vector plasmid pCR3-Flag (control group) were transfected into LS8 cells. Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay and cell cycle was detected by flow cytometry. All tests were repeated three times.Results:Compared with the control group (0.105±0.032), the proliferation activity of the wild group (0.201±0.009) was significantly higher after 72 h ( P<0.05). Compared with the control group (0.168±0.054) and the mutant group (0.194±0.059), the proliferation activity of the wild group (0.386±0.066) was significantly higher after 96 h ( P<0.05). There was no significant difference between the mutant group and the control group at all time points ( P>0.05). In the G 0/G 1 phase, compared with the control group (65.4%±2.1%) and the mutant group (66.6%±3.1%), the cell distribution ratio of the wild group (51.2%±1.1%) was significantly lower ( P<0.01). In the S phase, compared with the control group (23.1%±2.0%) and the mutant group (21.9%±1.8%), the cell distribution ratio of the wild type group (37.3%±2.4%) was significantly higher ( P<0.01). There was no significant difference in cell cycle distribution between the mutant group and the control group ( P<0.05). Conclusions:Wild EDA1 promotes the proliferation of LS8 cells and the transformation from G 0/G 1 to S phase. The syndrome mutant EDA1 (EDA1-H252L) loses its function of regulating the cell proliferation and cell cycle of LS8 cells.