Correlation analysis of phenotype and genotype of GJB2 in patients with non-syndromic hearing loss in China.

BACKGROUND: Disease-associated mutations in GJB2 gene are one of the major reasons that can cause non-syndromic sensorineural hearing loss (NSHL). GJB2 gene deafness has various clinical phenotypes. This study aims to analyze characteristics and relationships of clinical phenotypes through analyzing 1481 NSHL cases and 190 GJB2 deafness patients (with dual gene mutations). PATIENTS AND METHODS: All the patients diagnosed as deaf disease molecular diagnostics were obtained from the people's liberation army general hospital from March 2007 to March 2011. The accession number of GJB2 was NM_004004 in GenBank, and sequence alignment and annotation were performed using GeneTool software. RESULTS: In NSHL patients, mutated allele frequency in GJB2 was 20.57%, and the preponderant type was c.235delC (11.84%) followed by c.109G>A (3.75%). Mutation rate of double allelic gene was 16.18%, including 8.43% of homozygous mutation rate and 7.75% of recombination heterozygosis mutation. Moreover, auditory threshold of GJB2 biallelic marker was associated with ages of onset, while no significant correlation was detected with disease time and whether the inner ear malformation. Similar clinical phenotype could be detected between patients with c.109G>A dual gene mutation and dual gene mutation. However, in the aspect of hearing impairment, the phenomenon of pathopoiesia caused by mutation of c.109G>A was poorer than the other mutations, and even near those patients without pathogenic mutations. CONCLUSION: Our study further shows the definite relationship of clinical phenotype and genotype in GJB2 gene correlated deafness, and these results can provide basis for revealing pathogenesis, gene diagnosis and consult of deafness. The level of evidence in the study is level 4 (case series).

Clinical effect analysis of microscopic surgery for epiglottis cysts with coblation.

This study aims to explore the effects and advantages of coblation combined with microscopy to treat epiglottis cysts. Ninety patients with epiglottis cysts were randomly assigned to three groups: the first group: marsupialisation + electric coagulation group, n = 30; the second group: marsupialisation + coblation, n = 30; and the third group: marsupialisation + coblation + microsurgery, n = 30. To compare the cure rate, intraoperative bleeding volume, postoperative pain, operation time and postoperative complications were investigated among these three groups. The comparison among three procedures showed a significant difference for intraoperative bleeding volume, operation time and postoperative pain (P < 0.05), whereas no significant difference was observed for cure rate (P > 0.05). These three procedures are effective in treating epiglottis cysts. Microscopic surgery with coblation has the advantages of less bleeding, short procedure duration, less pain and few complications. Thus, microscopic surgery is worthy of clinical application.

A novel mutation in the TECTA gene in a Chinese family with autosomal dominant nonsyndromic hearing loss.

TECTA-related deafness can be inherited as autosomal-dominant nonsyndromic deafness (designated DFNA) or as the autosomal-recessive version. The α-tectorin protein, which is encoded by the TECTA gene, is one of the major components of the tectorial membrane in the inner ear. Using targeted DNA capture and massively parallel sequencing (MPS), we screened 42 genes known to be responsible for human deafness in a Chinese family (Family 3187) in which common deafness mutations had been ruled out as the cause, and identified a novel mutation, c.257-262CCTTTC>GCT (p. Ser86Cys; p. Pro88del) in exon 3 of the TECTA gene in the proband and his extended family. All affected individuals in this family had moderate down-sloping hearing loss across all frequencies. To our knowledge, this is the second TECTA mutation identified in Chinese population. This study demonstrates that targeted genomic capture, MPS, and barcode technology might broaden the availability of genetic testing for individuals with undiagnosed DFNA.

[Correlation study between obstructive level diagnosed by Apnea Graph and cephalometric posterior airway space in obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To study the correlation between Apnea Graph (AG) analysis of airway obstruction and cephalometric assessment of the posterior airway space in the diagnosis of obstructive level in patients with obstructive sleep apnea hypopnea syndrome (OSAHS), so as to improve the preoperative diagnostic accuracy and the therapeutic outcome. METHODS: Thirty patients (28 males and two females) who were diagnosed with severe OSAHS (mean AHI 58.6) by overnight polysomnography in recent 3 months were enrolled. The ages of the patients ranged from 35 to 59 years old with the median age of 41.5 years old. The mean body mass index (BMI, x(-) ± s) was (28.8 ± 4.1) kg/m(2). Mean apnea-hypopnea index (AHI) was (58.6 ± 16.4)/h. The lowest oxygen saturation was averaged to 0.69 ± 0.09. All patients underwent AG study as well as cephalometric analysis preoperatively. A correlation analysis was performed between the percentage of lower level obstructions measured by AG and the posterior airway space (PAS) evaluated by cephalometric analysis. RESULTS: All of the 30 patients had the obvious narrow PAS of 4.4 - 10.8 mm, with the average of (7.6 ± 2.1) mm. Their constituent ratios of lower level obstruction ranged from 2 to 87 percent with the median ratio of 15.5% [9.0%; 35.8%]. Among all the patients, only 2 cases had more than 50 percent obstruction of the airway at lower level, 8 cases had 30 to 40 percent obstruction, and 6 cases had the narrow PAS less than 6 mm. The constituent ratio of lower level obstructions had a negative rectilinear correlation with the data of PAS (r = -0.6511, P < 0.01), which meant the patient with a higher percentage of lower obstruction had the tendency to have a corresponding narrower PAS. Two cases whose constituent ratios of lower level obstructions were not compatible with the rectilinear tendency due to tonsillar hypertrophy were reported. CONCLUSIONS: AG analysis of airway obstruction and cephalometric assessment of the PAS could provide comparable and consistent results for the diagnosis of obstructive level in OSAHS. However, the tonsillar hypertrophy should be considered when using AG to identify the airway obstruction.