Multidimensional analysis of screening results of deafness susceptibility genes in 3066 newborns of different altitudes and nationalities in Xining, Qinghai(ISRCTN89197487)

1. Overall level: The overall carriage rate of deafness susceptibility genes in neonates from Xining, Qinghai is significantly lower than the national average for newborns (6.67%). Within the medium and high altitude regions of Qinghai Province, compared with the medium-altitude areas (altitude > 1,500 meters and ≤ 2,500 meters), the carriage rate of deafness susceptibility genes in neonates from high-altitude areas (altitude > 2,500 meters and ≤ 4,500 meters) shows a downward trend, which suggests that within the medium and high altitude range of the province, the detection rate of deafness susceptibility genes decreases with the increase of altitude. 2. Gene level: Among GJB2 gene mutations, the 235 delC gene mutation remains the most dominant type, and the detection rates of both GJB2 and GJB3 genes are lower than the national level. Notably, the detection rates of mitochondrial 12S rRNA gene mutations and SLC26A4 gene mutations in neonates from this region are both higher than the national average, with the detection rate of mitochondrial 12S rRNA gene mutations being more significantly higher. Since deafness caused by these two types of gene mutations can be effectively reduced in terms of onset risk through health education, conducting genetic testing targeting these specific genes has important clinical significance and public health value. 3. Ethnic background level: The detection rate of deafness susceptibility genes in Tibetan neonates is low, especially for the IVS7-2 A > G mutation site, and this phenomenon is more prominent in high-altitude areas. On the contrary, the detection rate of deafness susceptibility genes in Mongolian and Hui neonates in high-altitude areas shows an increasing trend.