Study of generational risk in deafness inflicted couples using deafness gene microarray technique / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To explored the significance of screening the gene mutations of deafness related in deaf-mute (deaf & dumb) family using DNA microarray.</p><p><b>METHODS</b>Total of 52 couples of deaf-mute were recruited from Changchun deaf-mute community. With an average age of (58.3 ± 6.7) years old (x(-) ± s). Blood samples were obtained with informed consent. Their genomic DNA was extracted from peripheral blood and PCR was performed. Nine of hot spot mutations in four most common deafness pathologic gene were examined with the DNA microarray, including GJB2, GJB3, PDS and mtDNA 12S rRNA genes. At the same time, the results were verified with the traditional methods of sequencing. Fifty of normal people served as a control group.</p><p><b>RESULTS</b>All patients were diagnosed non-syndromic sensorineural hearing loss by subjective pure tone audiometry. Thirty-two of 104 cases appeared GJB2 gene mutation (30.7%), the mutation sites included 35delG, 176del16, 235delC and 299delAT. Eighteen of 32 cases of GJB2 mutations were 235delC (59.1%). Seven of 104 cases appeared SLC26A4 gene IVS7-2 A > G mutation. Questionnaire survey and gene diagnosis revealed that four of 52 families have deaf offspring (7.6%). When a couple carries the same gene mutation, the risk of their children deafness was 100%. The results were confirmed with the traditional methods of sequencing.</p><p><b>CONCLUSIONS</b>There is a high risk of deafness if a deaf-mute family is planning to have a new baby. It is very important and helpful to avoid deaf newborns again in deaf-mute family by DNA microarray.</p>

Study on the genetic damage in mice induced by the volatile organic compounds of decoration materials / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study genetic damage of mice caused by the volatile organic compounds (VOC) of decoration materials.</p><p><b>METHODS</b>Fifty-five hotel guest rooms newly decorated within 6 months and 18 hotel guest rooms not decorated within 3 years were selected to determine the concentrations of 6 main VOC (benzene, methylbenzene, dimethylbenzene, ethyl acetate, butyl acetate, formaldehyde) in the air. Mice were exposed to VOC with the concentrations of 5, 10, 20, 40 times respectively as high as those present in the newly decorated rooms in an exposure cabinet for 15 days. DNA damage of peripheral lymphocytes of the mice was determined by single cell gel electrophoresis (SCGE) and bone marrow micronucleus test.</p><p><b>RESULTS</b>The concentrations of benzene, methylbenzene, dimethylbenzene, ethyl acetate, butyl acetate and formaldehyde in the rooms newly decorated within 6 months (6.50, 3.00, 6.70, 41.33, 1.70 and 0.14 mg/m(3) respectively) were significantly higher than those in rooms not decorated within 3 years (0.08, 0.94, 1.38, 0.25, 0.25, 0.01 mg/m(3), P < 0.01). DNA damage rates of peripheral lymphocytes in the concentrations of 10, 20, 40 times of exposure groups were significantly higher than those in the control groups (P < 0.05 or P < 0.01), and the frequencies of micronucleus in the mice exposed to 40 times of concentration was significantly higher than that in control group.</p><p><b>CONCLUSION</b>High concentrations of the volatile organic chemical compounds may cause genetic damage in mice. SCGE test is more sensitive than micronucleus test.</p>