title: The POLG Polyglutamine Tract Variants in Iranian Patients with Multiple Sclerosis.
abstract: OBJECTIVE
  Multiple Sclerosis (MS) is a common disease of the central nervous system. The interaction between inflammatory and neurodegenerative processes typically results in irregular neurological disturbances followed by progressive disability. Mitochondrial dysfunction has been implicated in neurodegenerative disorders. The DNA polymerase-gamma (POLG) gene, which encodes the catalytic subunit of enzyme responsible for directing mtDNA replication, contains a poly glutamine tract (poly-Q) in the N-terminal, encoded by a CAG sequence in exon 2.
  
  
  METHODS
  We analyzed the POLG trinucleotide repeats in 40 Iranian patients with MS (27 females and 13 males with an age range of 18-55); and 47 healthy age, gender, and ethnic matched controls were chosen by PCR-SSCP analysis.
  
  
  RESULTS
  Our results indicated that the most common allele in patients had 10 consecutive CAG repeats (10Q). Other alleles of 11and 12 trinucleotide repeats were detected. We did not find any difference between the CAG repeat length distribution in controls and MS patients.
  
  
  CONCLUSIONS
  No correlation was observed in the POLG gene CAG repeat with pathogenesis of MS, but it looks that other point mutations in POLG gene may have an important role in the disease's pathogenesis and produced more significant results.
authors.affiliation: Department of Biology, Faculty of Science, Yazd University, Yazd, Iran.
authors.forename: Mehri
authors.initials: M
authors.lastname: Khatami
authors.affiliation: Department of Biology, Faculty of Science, Yazd University, Yazd, Iran.
authors.forename: Mohammad Mehdi
authors.initials: MM
authors.lastname: Heidari
authors.affiliation: Department of Immunology, Shahid Sadoughi University of Medical Science, Yazd, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Mansouri
authors.affiliation: Department of Biology, Faculty of Science, Yazd University, Yazd, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Mousavi
keywords: CAG repeats; Multiple sclerosis; POLG gene; Trinucleotide expansion