RESUMEN

PURPOSE: We aim to report a genetic testing and fertility guidance for the deaf through analyzing pedigree and molecular genetic characteristics of the couple who have non-syndromic sensorineural hearing loss (NSHL). METHODS: One of hospitalized congenial deaf couple and family members were included in this study. The wife was twin pregnant woman and her gestational age was 31(+5) pregnant weeks. The DNA was extracted from peripheral blood and umbilical vein blood, respectively. Mutation screening of common deafness genes was performed in pregnant women and other family members. Nine common mutations in four major deafness genes, GJB2 (35delG, 176del16, 235delC, 299delAT), GjB3 (C538T), SLC26A4 (IVS7-2A>G, A2168G) and Mitochondrial 12S rRNA (A1555G, C1494T), were detected simultaneously with a microarray based method. SLC26A4 whole genome sequencing was carried out for the results of the DNA microarray. According to the test results, the couple chose abortion termination of pregnancy twins, and after one year obtained singleton pregnancy by artificial insemination by donor (AID). In week 16 of pregnancy, amniocentesis had been done to collect fetal somatic cell and extract DNA, and then the above tests had been repeated. RESULTS: The couple had SLC26A4 combined heterozygous mutation. Both parents had SLC26A4 single heterozygous mutation. Twin fetuses had SLC26A4 combined heterozygous mutation. The probability of naturally being pregnant and bearing deaf children for the pregnant women was 100%. Fetus obtained by AID had SLC26A4 single heterozygous mutation. After the birth of the baby, her hearing has been normal. CONCLUSIONS: To reduce children with congenital deafness, screening high mutation sites by microarray, combined with pedigree analysis and gene sequencing is effective, and should be used as a routine inspection item for the deaf before marriage and pregnancy. On the basis of genetic testing for the couple with hearing loss, human assisted reproductive technology is a viable option to avoid the birth of infant with hereditary deafness.