title: The sperm protamine mRNA ratio as a clinical parameter to estimate the fertilizing potential of men taking part in an ART programme.
abstract: OBJECTIVE
  Could the protamine-1 to protamine-2 mRNA ratio serve as a biomarker to estimate the fertilizing capacity of sperm from men taking part in an IVF/ICSI programme?
  
  
  CONCLUSIONS
  The protamine mRNA ratio clearly discriminates between fertile and subfertile men and sperm with a normal protamine mRNA ratio exhibit a higher fertilizing capacity in IVF/ICSI.
  
  
  BACKGROUND
  Aberrant sperm protamine ratios are associated with male factor infertility and mRNA ratio is comparable with protein ratio (due to transcriptional stop in elongating spermatids).
  
  
  METHODS
  The study population was drawn from subfertile men, whose female partners participated in IVF or ICSI programmes between September 2010 and February 2012. Normozoospermic healthy volunteers served as controls. Sperm cells were lysed, mRNA extracted, reverse transcribed and subjected to real-time quantitative PCR using specific primer pairs for protamine-1 and protamine-2. Relative protamine-1 and protamine-2 mRNA levels were analysed with the Mann-Whitney U-test (two-tailed).
  
  
  METHODS
  Quantitative RT-PCR for protamines 1 and 2 has been performed in ejaculates from 32 normozoospermic volunteers (control, University Clinic Giessen, Germany) and 306 patients, whose female partners took part in an IVF (n = 76; University Clinic Hamburg, Germany and Shanghai Jiaotong University, China) or an ICSI (n = 230; University Clinic Munich, Germany and Kinderwunschzentrum Wiesbaden, Germany) programme.
  
  
  RESULTS
  The sperm protamine mRNA ratio in normozoospermic men (0.98 ± 0.3) differed significantly from that of ICSI patients (Munich 0.81 ± 0.1; Wiesbaden 0.78 ± 0.2; P < 0.001), while processed samples obtained from IVF patients revealed a normal protamine mRNA ratio (Hamburg 1.0 ± 0.07; Shanghai 1.0 ± 0.54). Normal protamine mRNA ratios were associated with a significantly higher total motile sperm count and a significantly higher percentage of progressively motile sperm. Sperm with a normal protamine mRNA ratio revealed a higher fertilization capacity (fc) in both IVF (53.6% of patients with fc > 80%; P = 0.017) and ICSI (65.1% of patients with fc > 70%; P = 0.028).
  
  
  CONCLUSIONS
  The protamine mRNA ratio in an individual sperm cell used for ICSI may be different from the overall value obtained from a semen aliquot.
  
  
  CONCLUSIONS
  Data are in line with current literature and suggest the protamine mRNA ratio as a diagnostic marker to estimate the fertilizing capacity of sperm.
  
  
  BACKGROUND
  The German Research Foundation (DFG) to K.S., W.W. and A.P. (STE 892/9-2), as well as to A.S. and H.C.O. (SP721/1-3).
  None.
authors: Division of Gynecological Endocrinology and Reproductive Medicine, Department of Gynecology and Obstetrics, Klinikum der Ludwig-Maximilians-Universität, Campus Grosshadern, Munich, Germany.
authors: Nina
authors: N
authors: Rogenhofer
authors: Temuujin
authors: T
authors: Dansranjavin
authors: Martin
authors: M
authors: Schorsch
authors: Andrej
authors: A
authors: Spiess
authors: Hongxiang
authors: H
authors: Wang
authors: Viktoria
authors: V
authors: von Schönfeldt
authors: Heike
authors: H
authors: Cappallo-Obermann
authors: Vera
authors: V
authors: Baukloh
authors: Hao
authors: H
authors: Yang
authors: Agnieszka
authors: A
authors: Paradowska
authors: Bin
authors: B
authors: Chen
authors: Christian J
authors: CJ
authors: Thaler
authors: Wolfgang
authors: W
authors: Weidner
authors: Hans-Christian
authors: HC
authors: Schuppe
authors: Klaus
authors: K
authors: Steger
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D005260:Female; D005306:Fertilization / Q000502:physiology*; D005307:Fertilization in Vitro; D006801:Humans; D007248:Infertility, Male / Q000235:genetics / Q000378:metabolism; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D018873:Pregnancy Rate; D011479:Protamines / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D020554:Sperm Injections, Intracytoplasmic; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000378:metabolism*
chemical_list: D015415:Biomarkers; C082073:PRM1 protein, human; D011479:Protamines; D012333:RNA, Messenger; C068621:protamine 2