Objective  The goal of this research was to investigate the gap junction beta 2 ( GJB2 ) gene mutations associated with nonsyndromic hearing loss individuals in North Karnataka, India. Materials and Methods  For this study, patients with sensorineural genetic hearing abnormalities and a family history of deafness were included. A total of 35 patients from 20 families have been included in the study. The patient\'s DNA was isolated from peripheral blood samples. The GJB2 gene coding region was analyzed through Sanger sequencing. Results  There is no changes in the first exon of the GJB2 gene. Nine different variants were recorded in second exon of the targeted gene. W24X and W77X are two nonsense mutations and three polymorphisms viz. R127H, V153I, and I33T were reported along with four 3\'-UTR variants. A total (9/20) of 45% of families have been identified with mutations in the targeted gene. Conclusion   GJB2 mutations were identified in 19 deaf-mute patients (19/35), and 13 patients were homozygous for the mutations identified in our study cohort. In our study, W24X mutation was found to be the pathogenic with a high percentage, prompting further evaluation of the other genes, along with the study of additional genetic or external causes in the families, which is essential.

Objective:To analyze the genetic characteristics in nonsyndromic hearing impairment (NSHL) patients in Zhejiang province.Method:Peripheral blood samples were obtained from 1822 NSHL patients and 467 normal hearing controls in Zhejiang province. We carried out a systematic mutational screening of GJB2 gene in these subjects by amplifying the coding region of GJB2 gene and sequencing directly.Result:Thirty kinds of mutation were identified, including eleven pathogenic mutations, one hypomorphic allele, sixteen polymorphic mutations and two novel mutations. The c.235delC mutation was the most prevalent pathogenic mutation in this cohort (18.50%), and the rate of allele mutation was 12.16%. The frequency of c.299_300delAT,c.176_191del16,c.512_513insAACG,c.35delG,c.283G>A,c.427C>T,c.35insG,c.439G>A,c.571T>C,c.139G>T mutations were decreased in turn.Conclusion:c.235delC mutation is the hot spot of GJB2 gene mutation in NSHL patients in Zhejiang province and the most common mutational pattern is frame-shift mutation. The discovery of novel mutations enriches the spectrum and frequency of variants in GJB2 gene.

Hearing impairment (HI) is one of the leading causes of disability in the world, impacting the social, economic, and psychological well-being of the affected individual. This is particularly true in sub-Saharan Africa, which carries one of the highest burdens of this condition. Despite this, there are limited data on the most prevalent genes or mutations that cause HI among sub-Saharan Africans. Next-generation technologies, such as targeted genomic enrichment and massively parallel sequencing, offer new promise in this context. This study reports, for the first time to the best of our knowledge, on the prevalence of novel mutations identified through a platform of 116 HI genes (OtoSCOPE®), among 82 African probands with HI. Only variants OTOF NM_194248.2:c.766-2A>G and MYO7A NM_000260.3:c.1996C>T, p.Arg666Stop were found in 3 (3.7%) and 5 (6.1%) patients, respectively. In addition and uniquely, the analysis of protein-protein interactions (PPI), through interrogation of gene subnetworks, using a custom script and two databases (Enrichr and PANTHER), and an algorithm in the igraph package of R, identified the enrichment of sensory perception and mechanical stimulus biological processes, and the most significant molecular functions of these variants pertained to binding or structural activity. Furthermore, 10 genes (MYO7A, MYO6, KCTD3, NUMA1, MYH9, KCNQ1, UBC, DIAPH1, PSMC2, and RDX) were identified as significant hubs within the subnetworks. Results reveal that the novel variants identified among familial cases of HI in Cameroon are not common, and PPI analysis has highlighted the role of 10 genes, potentially important in understanding HI genomics among Africans.