NOVEL MUTATIONS AND HAPLOTYPE ANALYSIS OF GENOMIC POLYMORPHISMS OF GJB2 AND GJB3 GENES ASSOCIATED WITH PROFOUND AND MODERATELY SEVERE HEARING LOSS IN PATIENTS FROM BASHKORTOSTAN
Dzhemileva LU*, Khidiyatova IM, Khabibullin RM, Khusnutdinova EK
*Corresponding Author: Dr. Lilya U. Dzhemileva, Institute of Biochemistry and Genetics, Russian Academy of Sciences, Prospect Octyabrya 69, 450054, Ufa, Russia; Tel: +07-3472-355255; Fax: +07-3472-356100; E-mail: Dzhemilev@anrb.ru
page: 41

MATERIALS AND METHODS

In Bashkortostan, we studied patients with hereditary or sporadic hearing loss and their relatives. The total amount of samples included 132 individuals from 58 fami­lies. Hearing was assessed by puretone threshold audio­metry, acoustic impedance measuring and by detection of otoacoustic emission. The genetic character of deafness was inferred from the genealogical data. In addition, the patient’s history was analyzed in order to exclude the prenatal and postnatal effects of environmental factors. Infections, injuries of the hearing system and administra­tion of ototoxic antibiotics were taken into account. We also analyzed 55 unrelated families without any disorders.

Genomic DNA was isolated from 10 mL of peripheral blood by the standard protocol [16]. The coding exons of the GJB2 and GJB3 genes were divided into four frag­ments, obtained by polymerase chain reaction (PCR) with already published primers [17]. The genetic markers used in this study were microsatellite repeat polymorphisms (CA repeats) and they were amplified using the primers already described [17-19]. The products were resolved by polyacrylamide gel electrophoresis (PAGE) in 9% gel, stained with ethidium bromide, and visualized in UV light.

We performed both single-strand conformation poly­morphism (SSCP) and nucleotide sequence analyses; a combination of them revealed other, different mutations in the GJB2 and GJB3 genes. All 132 samples were screened to detect mutations by SSCP analysis. Some of the confor­mation polymorphisms were sequenced. The distances between the GJB2 gene and polymorphic markers are given in Fig. 1.

Linkage disequilibrium values were estimated by using Yule’s co-efficient, i.e., DSt = (p11–p12)/ Op(p11+p12–2p11p12) where p11 is the frequency of allele A1 on chromosomes carrying allele B1, and p12 is the fre­quency of allele A1 on chromosomes carrying allele B2 [18].

The three locus haplotypes, D13S143, D13S292, D13S175, were determined by the maximum-likelihood method, via the EM algorithm, as implemented in the HAPLO package [19], and cross-checked by an appropri­ate computer program. Haplotype diversity and linkage disequilibrium were estimated by standard methods.

 

Fig. 1 Map of the chromosome 13 region, including GJB2. Distance (in Kb) between GJB2 and flanking loci are indicated below the line.

 

 

D13S143
          GJB2(CX26)
                   GJB6(CX30)
                             D13S175

                                     D13S292                                                                           SAP18
sdfg           39       0      34   85    110                                100Kb                                            1035




Number 26
Number 26 VOL. 26(2), 2023 All in one
Number 26
VOL. 26(2), 2023
Number 26
VOL. 26, 2023 Supplement
Number 26
VOL. 26(1), 2023
Number 25
VOL. 25(2), 2022
Number 25
VOL. 25 (1), 2022
Number 24
VOL. 24(2), 2021
Number 24
VOL. 24(1), 2021
Number 23
VOL. 23(2), 2020
Number 22
VOL. 22(2), 2019
Number 22
VOL. 22(1), 2019
Number 22
VOL. 22, 2019 Supplement
Number 21
VOL. 21(2), 2018
Number 21
VOL. 21 (1), 2018
Number 21
VOL. 21, 2018 Supplement
Number 20
VOL. 20 (2), 2017
Number 20
VOL. 20 (1), 2017
Number 19
VOL. 19 (2), 2016
Number 19
VOL. 19 (1), 2016
Number 18
VOL. 18 (2), 2015
Number 18
VOL. 18 (1), 2015
Number 17
VOL. 17 (2), 2014
Number 17
VOL. 17 (1), 2014
Number 16
VOL. 16 (2), 2013
Number 16
VOL. 16 (1), 2013
Number 15
VOL. 15 (2), 2012
Number 15
VOL. 15, 2012 Supplement
Number 15
Vol. 15 (1), 2012
Number 14
14 - Vol. 14 (2), 2011
Number 14
The 9th Balkan Congress of Medical Genetics
Number 14
14 - Vol. 14 (1), 2011
Number 13
Vol. 13 (2), 2010
Number 13
Vol.13 (1), 2010
Number 12
Vol.12 (2), 2009
Number 12
Vol.12 (1), 2009
Number 11
Vol.11 (2),2008
Number 11
Vol.11 (1),2008
Number 10
Vol.10 (2), 2007
Number 10
10 (1),2007
Number 9
1&2, 2006
Number 9
3&4, 2006
Number 8
1&2, 2005
Number 8
3&4, 2004
Number 7
1&2, 2004
Number 6
3&4, 2003
Number 6
1&2, 2003
Number 5
3&4, 2002
Number 5
1&2, 2002
Number 4
Vol.3 (4), 2000
Number 4
Vol.2 (4), 1999
Number 4
Vol.1 (4), 1998
Number 4
3&4, 2001
Number 4
1&2, 2001
Number 3
Vol.3 (3), 2000
Number 3
Vol.2 (3), 1999
Number 3
Vol.1 (3), 1998
Number 2
Vol.3(2), 2000
Number 2
Vol.1 (2), 1998
Number 2
Vol.2 (2), 1999
Number 1
Vol.3 (1), 2000
Number 1
Vol.2 (1), 1999
Number 1
Vol.1 (1), 1998

 

 


 About the journal ::: Editorial ::: Subscription ::: Information for authors ::: Contact
 Copyright © Balkan Journal of Medical Genetics 2006