title: Increased TERC gene copy number in amniocytes from fetuses with trisomy 18 or a sex chromosome aneuploidy.
abstract: OBJECTIVE
  Individuals with chromosomal aneuploidies tend to develop malignancies. Telomerase is an enzyme complex that lengthens telomeres and has enhanced expression in numerous malignancies; one of its components is encoded by the TERC gene. In this study, we evaluated the TERC gene copy number in amniocytes from fetuses with aneuploidy, other than trisomy-21.
  
  
  METHODS
  In this prospective, basic research study, fluorescence in situ hybridization (FISH) for the TERC gene (3q26) was applied to amniocytes retrieved from 14 fetuses with various aneuploidies and from a control group of 6 fetuses with a normal karyotype, to determine the TERC gene copy number.
  
  
  RESULTS
  The percentage of cells with more than two copies of the TERC gene was lowest in the control group (x3=1.2 ± 0.4%; x4=0 ± 0%), higher in the sex chromosome aneuploidies (x3=4 ± 3%; x4=0.7 ± 0.95%) and even higher in trisomy 18 (x3=10.6 ± 2.3; x4=4.6 ± 1.8). The differences were statistically significant (P<0.05).
  
  
  CONCLUSIONS
  The TERC gene copy number is increased in aneuploid amniocytes, which demonstrates their genetic instability and is presumably related to their tendency to develop malignancies.
authors: Department of Obstetrics and Gynecology, Meir Medical Center, Kfar Saba, Israel.
authors: Tal
authors: T
authors: Biron-Shental
authors: Yona
authors: Y
authors: Kitay-Cohen
authors: Tamar
authors: T
authors: Tene
authors: Reuven
authors: R
authors: Sharony
authors: Aliza
authors: A
authors: Amiel
mesh_terms: D000653:Amniotic Fluid / Q000166:cytology / Q000378:metabolism; D000782:Aneuploidy; D016022:Case-Control Studies; D002887:Chromosomes, Human, Pair 18; D041321:Chromosomes, Human, X; D041322:Chromosomes, Human, Y; D005260:Female; D005333:Fetus / Q000378:metabolism; D018628:Gene Dosage; D042822:Genomic Instability; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D011247:Pregnancy; D011446:Prospective Studies; D012313:RNA / Q000235:genetics*; D012729:Sex Chromosome Aberrations; D019098:Telomerase / Q000235:genetics*; D014314:Trisomy
chemical_list: C422952:telomerase RNA; D012313:RNA; D019098:Telomerase