title: Molecular and clinical investigation of Iranian patients with Friedreich ataxia.
abstract: Friedreich ataxia (FRDA) is an autosomal recessive disorder caused by guanine-adenine-adenine (GAA) triplet expansions in the FXN gene. Its product, frataxin, which severely reduces in FRDA patients, leads to oxidative damage in mitochondria. The purpose of this study was to evaluate the triple nucleotide repeated expansions in Iranian FRDA patients and to elucidate distinguishable FRDA clinical differences in these patients.
  
  
  
  A number of 22 Iranian patients (8 females and 14 males) from 16 unrelated families were studied. DNA was extracted from the peripheral blood of patients. The frequency and length of (GAA)n repeats in intron 1 of the FXN gene were analyzed using long-range PCR. In this study, the clinical criteria of FRDA in our patients and the variability in their clinical signs were also demonstrated.
  
  
  
  An inverse relationship was observed between GAA repeat size and the age of onset. Although some distinguishable clinical features (such as limb ataxia and lower limb areflexia) were found in our patients, 90-95% of them had extensor plantar response and dysarthria. The results showed only one positive diabetes patient and also different effects on eye movement abnormality among our patients.
  
  
  
  The onset age of symptoms showed a significant inverse correlation with allele size in our patients (P>0.05). Based on comparisons of the clinical data of all patients, clinical presentation of FRDA in Iranian patients did not differ significantly from other FRDA patients previously reported.
authors.affiliation: Dept. of Molecular Genetics, Tarbiat Modares University, Tehran, Iran.
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Salehi
authors.affiliation: Dept. of Medical Genetics, National Institute for Genetic Engineering and Biotechnology, Tehran, Iran.
authors.forename: Massoud
authors.initials: M
authors.lastname: Houshmand
authors.affiliation: Dept. of Medical Genetics, Special Medical Center, Tehran, Iran.
authors.forename: Omid
authors.initials: O
authors.lastname: Aryani
authors.affiliation: Dept. of Pharmacy, Faculty of Medicine, University of Malaya, Malaysia.
authors.forename: Behnam
authors.initials: B
authors.lastname: Kamalidehghan
authors.forename: Elham
authors.initials: E
authors.lastname: Khalili
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D001259:Ataxia / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D004247:DNA / Q000032:analysis; D018450:Disease Progression; D004401:Dysarthria / Q000235:genetics; D005260:Female; D005621:Friedreich Ataxia / Q000175:diagnosis / Q000235:genetics*; D006801:Humans; D007492:Iran; D033862:Iron-Binding Proteins / Q000235:genetics*; D008297:Male; D008928:Mitochondria / Q000473:pathology; D001405:Reflex, Babinski / Q000235:genetics; D018911:Trinucleotide Repeats / Q000235:genetics*; D055815:Young Adult; D000096923:Frataxin
chemical_list: D004247:DNA; D033862:Iron-Binding Proteins; D000096923:Frataxin