title: Genome instability in AZFc region on Y chromosome in leukocytes of fertile and infertile individuals following exposure to gamma radiation.
abstract: OBJECTIVE
  Men are exposed to various doses of ionizing radiation due to living in regions with high natural background radiation, accidentally, occupationally or for cancer treatment. To study genomic instability of AZFc region to gamma radiation, blood samples from normal, oligozoospermia, and azoospermia individuals were irradiated by a Co-60 source.
  
  
  METHODS
  Irradiated cells were kept for 48 h in order to repair initial DNA damages. Real time PCR was performed for three markers (SY 1206, SY 1197, SY 579) for testing copy number variation before and after irradiation. Copy number variations were compared by calculation of cycle threshold comparative method.
  
  
  RESULTS
  Copy number variations of studied markers in AZFc region (microdeletion and duplication) in all samples after exposure to radiation increased with a dose dependent fashion. The frequency of instability was significantly higher in samples from infertile men in comparison with fertile ones (p < 0.001).
  
  
  CONCLUSIONS
  No significant difference was seen between the two infertile groups (p > 0.05). This observation might be a possible explanation for induction of azoospermia and oligozoospermia after radiotherapy. Increased frequency of induced microdeletion and duplication in infertile men compared with normal might be attributed to the deficiency in repair systems and the genetic factors involved in incomplete spermatogenesis of infertile men.
authors: Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, P.O.Box: 14115-111, Tehran, Iran.
authors: Sahar
authors: S
authors: Moghbeli-Nejad
authors: Hossein
authors: H
authors: Mozdarani
authors: Mehrdad
authors: M
authors: Behmanesh
authors: Zahra
authors: Z
authors: Rezaiean
authors: Parvin
authors: P
authors: Fallahi
mesh_terms: D053713:Azoospermia / Q000097:blood / Q000235:genetics*; D041322:Chromosomes, Human, Y / Q000235:genetics*; D003036:Cobalt Isotopes / Q000009:adverse effects; D056915:DNA Copy Number Variations / Q000235:genetics / Q000528:radiation effects; D005720:Gamma Rays / Q000009:adverse effects; D042822:Genomic Instability / Q000528:radiation effects; D006801:Humans; D007248:Infertility, Male / Q000235:genetics*; D007962:Leukocytes / Q000528:radiation effects; D008297:Male; D009845:Oligospermia / Q000097:blood / Q000235:genetics*
chemical_list: D003036:Cobalt Isotopes