The spectrum of GJB2 mutations in the Iranian population with non-syndromic hearing loss—A twelve year study

Bazazzadegan, Niloofar; Nikzat, Nooshin; Fattahi, Zohreh; Nishimura, Carla; Meyer, Nicole C.; Sahraian, Shima; Jamali, Payman; Babanejad, Mojgan; Kashef, Atie; Yazdan, Hilda; Kermani, Farahnaz Sabbagh; Taghdiri, Maryam; Azadeh, Batool; Mojahedi, Faezeh; Khoshaeen, Atefeh; Habibi, Haleh; Reyhanifar, Farahnaz; Nouri, Nayereh; Smith, Richard J.H.; Kahrizi, Kimia; Najmabadi, Hossein

doi:10.1016/j.ijporl.2012.04.026

Cited by 41 publications

(48 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Accepting the northwest‐to‐southeast GJB2 HL gradient throughout Iran, our data indicates a west‐to‐east gradient among Iranian populations with a GJB2 mutations frequency of 31.2% for Isfahan province and 7.5% for Yazd province. The results obtained from other studies have shown that the mutation frequency of GJB2 varies between 0% and 35% within different parts of Iran (Bazazzadegan et al., ). The study performed by Najmabadi et al.…”

Section: Discussionmentioning

confidence: 92%

GJB2‐related hearing loss in central Iran: Review of the spectrum and frequency of gene mutations

Koohiyan

Koohian

Azadegan‐Dehkordi

2019

Annals of Human Genetics

View full text Add to dashboard Cite

Mutations in the GJB2 gene are a main cause of autosomal-recessive nonsyndromic hearing loss (ARNSHL) in many populations. Previous studies have estimated the average frequency of GJB2 mutations to be ∼16% in Iran, but would vary among different ethnic groups. Here, we have taken together and reviewed results from our two previous publications and data from searching other published mutation reports to provide a comprehensive collection of data for GJB2 mutations and HL in central Iran. In all, 332 unrelated families were included and analyzed for the prevalence and type of the GJB2 gene mutations. In total, the frequency of GJB2 mutations was found to be 16% in the central provinces, which is significantly higher than those identified in southern populations of Iran. Also, c.35delG was the most frequent mutation in the related population. The present study suggests that mutations in the GJB2 gene, especially c.35delG, are important causes of HL in central Iran and can be used as a basis of genetic counseling and clinical guidelines in this region.

show abstract

Section: Discussionmentioning

confidence: 92%

GJB2‐related hearing loss in central Iran: Review of the spectrum and frequency of gene mutations

Koohiyan

Koohian

Azadegan‐Dehkordi

2019

Annals of Human Genetics

View full text Add to dashboard Cite

show abstract

“…primary immunodeficiencies resulting in increased susceptibility to infectious disease(s) [51,52] , or chronic childhood kidney disorders [53,54] . However, in terms of absolute numbers, recessive disorders that are common and not restricted to any single community, such as non-syndromic hearing impairment [55,56] and intellectual and developmental disabilities [57,58] , should show the most obvious future decline in prevalence.…”

Section: Consanguinity Postnatal Mortality and The Prevalence Of Genmentioning

confidence: 99%

Consanguineous Marriage, Reproductive Behaviour and Postnatal Mortality in Contemporary Iran

Hosseini-Chavoshi

Abbasi-Shavazi²,

Bittles³

2014

Hum Hered

View full text Add to dashboard Cite

Objectives: The aims of the study were to determine the prevalence, types and socio-economic correlates of consanguineous marriages in Iran, and to gauge the extent to which consanguinity influenced fertility, pregnancy outcomes and the expression of genetic disorders in the present-day population. Methods: Data on the prevalence of consanguinity and birth outcomes in the first marriages of 5,515 women were abstracted from the 2005 Iran Low Fertility Study [Hosseini-Chavoshi et al: Fertility and Contraceptive Use Dynamics in Iran: Special Focus on Low Fertility Regions. Canberra, Australian National University, 2007]. The results of associated socio-economic variables were collated and assessed by Pearson's χ² analysis and logistic regression. Results: Overall, 37.4% of the marriages were consanguineous (α = 0.0149), but with major differences between 4 representative populations. Consanguinity was higher among rural couples, older marriage cohorts, women marrying at a younger age, and women with lower levels of formal education. In general, consanguineous couples had higher mean numbers of pregnancies, live births and surviving children. Conclusions: Given declining family sizes, a rapid urbanization and increased educational and employment opportunities, it seems inevitable that consanguineous marriages will decline in prevalence in Iran, albeit more slowly in more traditional rural communities. Predictably, there will be a concomitant reduction in the incidence of recessive genetic disorders, but this is against a background transition from communicable to non-communicable diseases.

show abstract

“…For example, in Iran, the prevalence of GJB2 -related deafness is relatively low. It accounts for about 22% of severe-to-profound autosomal recessive NSHL (ARNSHL) in the Azerbaijan province of North-West Iran, but falls to about 8% in the South-Eastern Iranian provinces of Sistan and Baluchestan 13. In contrast, in multiple countries with a low coefficient of inbreeding, variants in GJB2 -related deafness account for about 50% of congenital severe-to-profound ARNSHL 14 15…”

Section: Introductionmentioning

confidence: 99%

Characterising the spectrum of autosomal recessive hereditary hearing loss in Iran

et al. 2015

Self Cite

View full text Add to dashboard Cite

Background Countries with culturally accepted consanguinity provide a unique resource for the study of rare recessively inherited genetic diseases. Although hereditary hearing loss (HHL) is not uncommon, it is genetically heterogeneous, with over 85 genes causally implicated in non-syndromic hearing loss (NSHL). This heterogeneity makes many gene-specific types of NSHL exceedingly rare. We sought to define the spectrum of autosomal recessive HHL in Iran by investigating both common and rarely diagnosed deafness-causing genes. Design Using a custom targeted genomic enrichment (TGE) panel we simultaneously interrogating all known genetic causes of NSHL in a cohort of 302 GJB2-negative Iranian families. Results We established a genetic diagnosis for 67% of probands and their families, with over half of all diagnoses attributable to variants in five genes: SLC26A4, MYO15A, MYO7A, CDH23, and PCDH15. As a reflection of the power of consanguinity mapping, 26 genes were identified as causative for NSHL in the Iranian population for the first time. In total, 179 deafness-causing variants were identified in 40 genes in 201 probands, including 110 novel single nucleotide or small insertion-deletion variants and 3 novel copy number variations. Several variants represent founder mutations. Conclusion This study attests to the power of TGE and massively parallel sequencing (TGE+MPS) as a diagnostic tool for the evaluation of hearing loss in Iran, and expands on our understanding of the genetics of HHL in this country. Families negative for variants in the genes represented on this panel represent an excellent cohort for novel gene discovery.

show abstract

The spectrum of GJB2 mutations in the Iranian population with non-syndromic hearing loss—A twelve year study

Cited by 41 publications

References 18 publications

GJB2‐related hearing loss in central Iran: Review of the spectrum and frequency of gene mutations

GJB2‐related hearing loss in central Iran: Review of the spectrum and frequency of gene mutations

Consanguineous Marriage, Reproductive Behaviour and Postnatal Mortality in Contemporary Iran

Characterising the spectrum of autosomal recessive hereditary hearing loss in Iran

Contact Info

Product

Resources

About