Subaşıoğlu Aslı, Duman Duygu, Sırmacı Aslı, Bademci Güney, Carkıt Fehime, Somdaş Mehmet Akif, Erkan Mustafa, Tekin Mustafa, Dündar Munis
Department of Medical Genetics, Erciyes University Faculty of Medicine, Kayseri, Turkey.
Department of Pediatrics, Division of Pediatric Genetic Diseases, Ankara University Faculty of Medicine, Ankara, Turkey.
Turk Pediatri Ars. 2017 Sep 1;52(3):122-132. doi: 10.5152/TurkPediatriArs.2017.4254. eCollection 2017 Sep.
Hearing loss is the most common sensory disorder that affects approximately one per 1000 live births. With this project, we aimed to identify gene variants that were common causes of hearing loss in Turkey to contribute to the planning of genetic screening programs for hearing loss, as well as to improve genetic counseling to affected families.
Twenty-one families with at least two affected individuals and parental consanguinity who presented with non-syndromic severe-to-profound sensorineural hearing loss were included in this study. We first screened for mutations in GJB2 and mitochondrial DNA 12S RNA genes. Subsequently, we genotyped the TMIE c.250C>T and SNP markers flanking the genes in the remaining twelve families without mutations in GJB2.
Screening for mutations in GJB2 gene showed c.[35delG];[35delG] mutation in four families, c.[35delG];[507C>A] mutation in two families, c.[35delG];[-23+1G>A] mutation in one family, and c.457G>A heterozygous mutation in one family. Genotyping SNP markers showed the c.[250C>T];[250C>T] mutation in TMIE in one family. A homozygous region with SNP genotypes was detected with the gene in one family, the gene in another family, and also a homozygous region was detected with , and genes in another family.
Further research will be required to determine the genetic bases of hearing loss in families with non-syndromic hearing loss.
听力损失是最常见的感觉障碍，每1000例活产中约有1例受影响。通过本项目，我们旨在确定土耳其听力损失的常见基因变异，以促进听力损失基因筛查项目的规划，并改善对受影响家庭的遗传咨询。
本研究纳入了21个家庭，这些家庭至少有两名受影响个体且父母为近亲，均表现为非综合征性重度至极重度感音神经性听力损失。我们首先筛查了GJB2和线粒体DNA 12S RNA基因的突变。随后，我们对其余12个GJB2基因无突变的家庭中的TMIE基因c.250C>T及侧翼的单核苷酸多态性（SNP）标记进行了基因分型。
GJB2基因突变筛查显示，4个家庭存在c.[35delG];[35delG]突变，2个家庭存在c.[35delG];[507C>A]突变，1个家庭存在c.[35delG];[-23+1G>A]突变，1个家庭存在c.457G>A杂合突变。SNP标记基因分型显示，1个家庭的TMIE基因存在c.[250C>T];[250C>T]突变。在1个家庭中检测到与该基因相关的SNP基因型纯合区域，在另1个家庭中检测到与该基因相关的纯合区域，在另1个家庭中还检测到与该基因、该基因及该基因相关的纯合区域。
对于非综合征性听力损失家庭，需要进一步研究以确定听力损失的遗传基础。
