title: GJB2 and GJB6 genes and the A1555G mitochondrial mutation are only minor causes of nonsyndromic hearing loss in the Qatari population.
abstract: OBJECTIVE
  This study reports results from the first survey of the genetic causes of nonsyndromic sensorineural hearing loss (NSHHL) in the Qatari population. DESIGN AND STUDY SAMPLES: Data were collected from 126 Qatari patients (58 males and 68 females) belonging to inbred families (56%), showing an autosomal recessive pattern of inheritance (96%). Fifty-three patients were less than 10 years old, 55 in the age range of 10 to 20 years, while 18 were aged between 20 and 30 years. All subjects had moderate to severe sensorineural hearing loss and were screened for GJB2 mutations, GJB6 deletion, and for A1555G mitochondrial mutation.
  
  
  RESULTS
  Four patients were homozygous and one was heterozygous for c.35delG; five were homozygous for the IVS1 + 1G < A, and two were heterozygous for c.229 T > C. Only 8.3% of the pathogenic alleles were detected. No patients were positive for GJB6 deletion or for A1555G .
  
  
  CONCLUSIONS
  These findings: (1) demonstrate that GJB2, GJB6 deletion and A1555G mutation account for a minor proportion of NSHHL in the Qatari population, (2) further strengthen the need to search for causative genes, (3) clearly contribute to establishing preventive strategies for NSHHL in Qatar and in the Gulf area.
authors: Molecular Genetics Laboratory; Laboratory of Medicine and Pathology, Hamad Medical Corporation, Doha, Qatar.
authors: M
authors: M
authors: Khalifa Alkowari
authors: G
authors: G
authors: Girotto
authors: K
authors: K
authors: Abdulhadi
authors: S
authors: S
authors: Dipresa
authors: R
authors: R
authors: Siam
authors: N
authors: N
authors: Najjar
authors: R
authors: R
authors: Badii
authors: P
authors: P
authors: Gasparini
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26; D000075302:Connexin 30; D017630:Connexins / Q000235:genetics*; D004272:DNA, Mitochondrial; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation; D011780:Qatar; D055815:Young Adult
chemical_list: D000075302:Connexin 30; D017630:Connexins; D004272:DNA, Mitochondrial; C000607042:GJB2 protein, human; C491020:GJB6 protein, human; D000072259:Connexin 26