Nuray ALTINTAŞ, Seda ÖRENAY, Ali Vefa YÜCETÜRK

Investıgatıon of the 35delg mutatıon ın the gjb2 (connexın 26) gene-related famıly ın Manısa and vıcınıty ın Turkey

Günümüze kadar tüm popülasyonlarda yapılan çalışmalarda Connexin 26 (GJB2 ) genindeki mutasyonlar non sendromik otozomalresesif konjenital işitme kaybında önemli bir yere sahiptir. Connexin 26 geni ve mutasyon tipleriyle ilişkilendirilen işitme kaybını belirlemek için Türkiye’de Manisa ve yöresinde yaşayan 8 non- sendromik işitme kayıplı birey, akraba evliliğiyapmış 14 aile (evli çiftler) çalışmaya alınmıştır. 35delG mutasyonları polimeraz zincir reaksiyonu (PZR) ve kompetitif amplifikasyon refraktermutasyon sistemi (C-ARMS) ile belirlenmiştir. Yedihasta 35delG mutasyonu için homozigot, bir hastaheterozigot olarak saptanmıştır. Sonuçlarımız, Türkiye’de Manisa ve çevresindeki hastalarda nonsendromik konjenital işitme kaybına Connexin 26 genindeki 35delG mutasyonunun neden olduğunu ortaya koymuştur.

Türkiye’de Manisa ve yöresinde akraba evliliği yapmış ailelerde gjb2 (connexin 26) genindeki 35delg mutasyonunun araştırılması

Mutations in connexin 26 gene (GJB2)lead to a significant proportion of non-syndromicautosomal recessive congenital hearing loss in allpopulations studied so far. Eight patients with non-syndromic hearing loss out of 14 related family(marriage couple) were screened to determinehearing loss attributed to connexin 26 gene and thetypes of mutations living in Manisa and vicinity,Turkey. The 35delG mutations were detected byPolymerase Chain Reaction (PCR) with CompetitiveAmplification Refractory Mutation System (C-ARMS). Seven patients were detected as homozygousfor the 35delG mutation and one patient detected asheterozygous. Our results indicate that 35delGmutation in the connexin 26 gene was the cause ofnon-syndromic congenital hearing loss of thepatients in Manisa and vicinity in Turkey.

PDF

___

1. Mukherjee M, Phadke SR, Mittal B , Con- nexin 26 and autosomal recessive non- syndromic hearing loss. Indian Journal of Human Genetics 2003; 9: 40-50.
2. Schrijver I. Hereditary nonsyndromic sensorineural hearing loss: transforming silence to sound.J Mol Diagn. 2004;6:275– 284.
3. Yilmaz A, Menevse S, Bayazit Y ,et al. Two novel missense mutations in the Connexin 26 gene in Turkish patients with Nonsyndromic Hearing Loss. Biochem Genet 2010;48:248– 256.
4. Ay J, Rasool TJ. High frequency of connex- in26 (GJB2) mutations associated with non- syndromic hearing loss in the population of Kerala, India. Int J Pediatr Otorhinolaryn- gol. 2009;73:437-43.
5. Miller SA, Dykes DD, Polesky HF. A simple salting out procedure for extracting DNA from human nucleated cells. Nucleic Acides Research 1988;16:1215.
6. Zelante L, Gasparini P, Estivill X, Mel- chionda S, D'Agruma L, Govea N, Mila M, Monica, M.D, Lutfi J. Connexin26 mutations associated with the most common form of non -syndromic neurosensory autosomal reces- sive deafness (DFNB1) in Mediterraneans. Hum. Mol. Genet. 1997;6:1605-1609.
7. Kalay E, Caylan R, Kremer H, de Brouwer APM, Karaguzel A. GJB2 mutations in Turk- ish patients with ARNSHL: prevalence and two novel mutations. Hear Res. 2005;203:88- 93.
8. Baris I, Kilinc MO, Tolun A. Frequency of the 35delG mutation in the connexin 26 gene in Turkish hearing-impaired patients. Clin Genet. 2001;60:452-5.
9. Bayazit YA, Cable BB, Cataloluk O. GJB2 gene mutations causing familial hereditary deafness in Turkey. Int J Pediatr Otorhi- nolaryngol. 2003;67:1331-5.
10. Balci B, Gerceker FO, Aksoy S, et al. Identifi- cation of an ancestral haplotype of the 35delG mutation in the GJB2 (connexin 26) gene responsible for autosomal recessive non -syndromic hearing loss in families from the Eastern Black Sea Region in Turkey. Turk J Pediatr. 2005;47:213-21.
11. Fisioğlu H. Consanguineous marriage and marital adjustment in Turkey. The Family. Journal . 2001;9:215-222.
12. B a k i A , K a ra g ü z el A ,B e şe r E . Consanguineous marriages in the province of Trabzon. East African Medical Journal.1992;69:294-96.