Fig 1.
As shown in Figure, the overall detection rate of deafness-susceptible genes in this study was 5.38%.
Regarding genotype distribution, heterozygotes accounted for 4.83%, while homozygotes accounted for 0.55%, indicating that heterozygotes were the predominant type detected. In terms of gender, the carrier rate of deafness-susceptible genes was 5.36% in male infants and 5.40% in female infants. The rates were very similar, with only a 0.04% difference between males and females, both aligning closely with the overall detection rate (5.38%). The bars in the figure indicate the 95% confidence intervals (95% CIs) for each group’s results.
Table 1.
Shows the overall detection rates of a total of 15 loci in the four genes screened in this study.
Fig 2.
As shown in Figure, the distribution of detection rates for the four major deafness-related genes-GJB2, SLC26A4, mitochondrial 12S rRNA, and GJB3-is clearly illustrated.
Among these, GJB2 exhibited the highest detection rate at 2.38%, while GJB3 showed the lowest at 0.03%. The bars in the figure indicate the 95% confidence intervals (95% CIs) for each group’s results.
Fig 3.
The four figures above show the base sequence maps and locus mutations of the detected deafness-susceptible genes after rechecking.
Fig 4.
Ethnic Distribution of GJB2 Gene Mutation Carriers: As illustrated in the figure, among different ethnic groups, the detection rate of GJB2 gene mutations was highest in Mongolians, followed by Han, Tibetans, and Hui populations.
The bars in the figure indicate the 95% confidence intervals (95% CIs) for each group’s results.
Fig 5.
Altitude Distribution Characteristics of GJB2 Gene Mutations: As shown in the figure, GJB2 gene mutations were detected in both medium-altitude and high-altitude regions, with a relatively lower mutation rate observed in high-altitude areas.
The bars in the figure represent the 95% confidence intervals (95% CIs) for each group, and this convention applies throughout unless otherwise stated.
Fig 6.
Distribution of Mutation Rates at Four GJB2 Gene Loci: As shown in the figure, among all mutation loci of the GJB2 gene, the c.235delC locus exhibited the highest mutation rate at 1.60%, followed by the c.299_300delAT locus with a detection rate of 0.52%.
The c.35delG heterozygous variant and the c.176_191del16 heterozygous variant showed the same detection rate, both at 0.13%.
Fig 7.
Ethnic Distribution Characteristics of SLC26A4 Gene Mutation Detection Rates: As shown in the figure, among different ethnic groups, the detection rate of SLC26A4 gene mutations was highest in the Hui population, surpassing that of the Han group for the first time.
In contrast, the detection rate in the Tibetan population was significantly lower and remained at a relatively low level.
Fig 8.
Distribution of SLC26A4 Gene Detection Rates Across Different Altitude Regions: As shown in the figure, the detection rate of the SLC26A4 gene exhibited significant altitude-related variation.
Specifically, the detection rate in high-altitude areas was lower than that in medium-altitude areas. This distribution pattern was consistent with the trend observed for GJB2 gene detection rates across different altitude regions. For medium-altitude areas, the 95% confidence interval (95% CI) ranged from 0.0197 to 0.0327, while for high-altitude areas, it ranged from 0.0051 to 0.0215.
Fig 9.
Distribution of Detection Rates for Eight Mutation Sites in the SLC26A4 Gene: As shown in the figure, among the eight mutation sites of the SLC26A4 gene, the c.IVS7-2A > G site exhibited the highest mutation frequency, with a detection rate of 1.04%, followed by the c.1226G > A site, with a detection rate of 0.23%.
The IVS15 + 5G > A site showed the lowest detection rate, at only 0.07%.
Fig 10.
Distribution of Detection Rates for Homoplasmic and Heteroplasmic Mutations in the Mitochondrial 12S rRNA Gene: As shown in the figure, among the mutation types of the mitochondrial 12S rRNA gene, the detection rate of heteroplasmic mutations was relatively higher, at 0.62%, while that of homoplasmic mutations was 0.46%.
A noticeable difference in mutation frequency was observed between the two types.
Fig 11.
Distribution of Detection Rates of Mitochondrial 12S rRNA Gene Mutations Among Different Ethnic Groups: As shown in the figure, the detection rates of mitochondrial 12S rRNA gene mutations varied among different ethnic groups.
The highest detection rate was observed in the Tibetan population, followed by the Hui population, while the Han population exhibited the lowest detection rate.
Fig 12.
Distribution of Detection Rates of Mitochondrial 12S rRNA Gene Mutations in High- and Medium-Altitude Areas: As shown in the figure, the detection rates of mitochondrial 12S rRNA gene mutations were identical in both high-altitude and medium-altitude regions, each being 1.08%.
These results suggest that there was no statistically significant difference in the detection rates of this gene mutation between the two altitude regions.
Fig 13.
Distribution of Detection Rates of Major Mutation Sites in the Mitochondrial 12S rRNA Gene: As shown in the figure, among the two detected mutation sites of this gene, the c.1555A > G site exhibited a clearly dominant mutation frequency, with a detection rate of 1.04%.
In contrast, the c.1494C > T site showed a markedly lower detection rate of only 0.03%, indicating a significant difference in mutation frequency between the two sites.
Fig 14.
Distribution and detection rates of deafness-susceptible genes among different ethnic groups.
A: Distribution of the proportions of detected cases carrying deafness-susceptible genes among different ethnic groups. Among these groups, the Han population accounted for the largest proportion, reaching 69.70%, followed by the Tibetan and Hui populations, each representing 14.55%. The Mongolian population accounted for 1.21%. Additionally, 10 ethnic groups-including the Tu, Salar, Manchu, Kazakh, Buyi, Achang, Dongxiang, Uyghur, Miao, and Zhuang-had no detected carriers of deafness-susceptible genes and are therefore not shown in the figure. B: Comparison of the overall detection rates of deafness-susceptible genes among different ethnic groups. The results show that the Mongolian population exhibited the highest detection rate, at 6.67%, followed by the Han (5.80%), Hui (5.04%), and Tibetan (4.49%) populations. No deafness-susceptible genes were detected in the remaining ten ethnic groups.
Fig 15.
Comparison of Detection Rates of Deafness Genes Between Medium- and High-Altitude Areas Among Different Ethnic Groups: As shown in the figure, among Han and Tibetan newborns, the detection rates of deafness genes in high-altitude areas were lower than those in medium-altitude areas, with the rate among Tibetan newborns being particularly low.
In contrast, among Mongolian and Hui newborns, the detection rates in high-altitude areas were higher than those in medium-altitude areas, with a more pronounced difference observed in the Mongolian population. No deafness-susceptible genes were detected in the remaining ten ethnic groups.
Fig 16.
Distribution of Detection Rates of Various Gene Loci Among Han Newborns: As shown in the figure, the c.235delC locus of the GJB2 gene exhibited the highest detection rate among the Han population, reaching 1.87%.
This was followed by the c.IVS7-2A > G locus of the SLC26A4 gene, with a detection rate of 1.11%, and the c.1555A > G locus of the mitochondrial 12S rRNA gene, with a detection rate of 0.96%.
Fig 17.
Distribution of Detection Rates of Various Deafness-Susceptible Gene Mutation Loci in Tibetan Newborns: As shown in the figure, among the Tibetan population, the c.1555A > G locus in the mitochondrial 12S rRNA gene exhibited the highest detection rate, reaching 1.50%.
This was followed by the c.235delC locus in the GJB2 gene, with a detection rate of 1.31%, and the c.299_300delAT locus, with a detection rate of 0.93%.
Fig 18.
Comparison of Detection Rates of Deafness Genes Between Male and Female Newborns in the Hui Screening Population: As shown in the figure, the detection rate of deafness genes in male infants (6.30%) was notably higher than that in female infants (3.60%).
Fig 19.
Detection Rates of Deafness-Susceptible Gene Mutations in Hui Newborns: As shown in the figure, the distribution of detection rates for deafness-susceptible gene mutations among Hui newborns is presented.
The results indicate that the c.IVS7-2A > G locus in the SLC26A4 gene exhibited the highest detection rate, reaching 1.68%, followed by the c.1555A > G locus in the mitochondrial 12S rRNA gene, with a detection rate of 1.05%. The c.235delC locus in the GJB2 gene ranked third, with a detection rate of 0.84%.
Fig 20.
Comparison of Detection Rates of Deafness-Susceptible Genes Between Male and Female Mongolian Newborns: As shown in the figure, with a sample size of 12 cases in each group, the detection rate of deafness-susceptible genes in female infants was 11.11%, which was higher than that in male infants (6.67%).
Fig 21.
Distribution of Detection Rates of Deafness-Susceptible Genes in Mongolian Newborns: As shown in the figure, a total of two cases of deafness gene carriers were identified in the Mongolian population, both involving mutations in the GJB2 gene.
Specifically, the mutations were located at the c.235delC and c.299_300delAT loci, each with a detection rate of 4.17% (95% CI: < 0.0001-0.2187). No mutations were detected in other genes or loci.
Table 2.
Among the 165 neonates confirmed as carriers of deafness mutant genes after rechecking, the number of detected cases at deafness gene mutation loci among neonates of different ethnic groups is as follows.
Fig 22.
Comparison of Detection Rates of Deafness-Susceptible Gene Mutations Between Medium- and High-Altitude Areas: As shown in the figure, the detection rate of deafness-susceptible gene mutations in high-altitude areas (4.45%) was lower than that in medium-altitude areas (5.69%).
Fig 23.
Distribution of Detection Rates of Deafness-Susceptible Genes Among Newborns of Different Ethnic Groups in Medium-Altitude Areas: As shown in the figure, the Mongolian population exhibited the highest detection rate of deafness-susceptible genes (8.33%), followed by the Han population (5.96%).
The Tibetan population showed the lowest detection rate (4.43%).
Fig 24.
The distribution of mutation rates at different loci of the GJB2 gene in medium-altitude areas is shown in the figure.
The c.235delC locus exhibited the highest mutation rate, with a detection rate of 1.64% (95%), followed by the c.IVS7-2A > G locus, with a detection rate of 1.12% (95%), and the c.1555A > G locus, with a detection rate of 1.03% (95%).
Fig 25.
Distribution of Detection Rates of Deafness-Susceptibility Genes Among Different Ethnic Groups in High-Altitude Areas: As shown in the figure, the Mongolian newborns exhibited the highest detection rate of deafness-susceptibility genes in high-altitude regions, reaching 8.33% (95%).
The Hui population ranked second, with a detection rate of 5.68%, which was higher than that of the Han population (5.18%). The Tibetan population showed the lowest detection rate, at only 2.81% (95%). No deafness-susceptibility genes were detected among the other ethnic groups.
Fig 26.
Distribution of Mutation Detection Rates at Different Gene Loci in High-Altitude Areas.
Table 3.
Screening Data of Neonatal Deafness Genes in Various Provinces of China.