title: Synapsis and meiotic recombination analyses: MLH1 focus in the XY pair as an indicator.
abstract: BACKGROUND
  Anomalies in meiotic prophase I have been related to partial or total meiotic arrest. These anomalies include an abnormal synaptic process, resulting in disorders in meiotic recombination.
  
  
  METHODS
  In the present study, we analyse primary spermatocytes from 12 infertile men (four with non-obstructive azoospermia, six with oligoastenoteratozoospermia, one with astenoteratozoospermia and one normozoospermic) and five control fertile donors using immunocytological techniques for synaptonemal complex, meiotic recombination and centromeric proteins.
  
  
  RESULTS
  Mean numbers of MLH1 foci per cell, frequencies of cells presenting an MLH1 focus in the XY pair and percentages of cells affected by abnormal synaptic patterns (gaps and splits) are reported for each of the infertile patients and control men. A positive correlation between the frequency of cells showing a recombination focus in the XY pair and the number of autosomal recombination foci per cell is found.
  
  
  CONCLUSIONS
  Reduced recombination in the XY pair and an increased number of cells affected by gaps may explain some idiopathic male infertility cases. The results suggest that recombination in the XY pair could be an indicator for general recombination frequency and for a successful meiotic process.
authors.affiliation: Unitat de Biologia i Genètica Mèdica, Departament de Biologia Cel.lular, Fisiologia i Immunologia, Unitat de Bioestadística, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain. montserrat.codina@uab.es
authors.forename: Montserrat
authors.initials: M
authors.lastname: Codina-Pascual
authors.forename: Maria
authors.initials: M
authors.lastname: Oliver-Bonet
authors.forename: Joaquima
authors.initials: J
authors.lastname: Navarro
authors.forename: Mercè
authors.initials: M
authors.lastname: Campillo
authors.forename: Ferran
authors.initials: F
authors.lastname: García
authors.forename: Susana
authors.initials: S
authors.lastname: Egozcue
authors.forename: Carlos
authors.initials: C
authors.lastname: Abad
authors.forename: Josep
authors.initials: J
authors.lastname: Egozcue
authors.forename: Jordi
authors.initials: J
authors.lastname: Benet
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000906:Antibodies; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D018914:Cells, Immobilized; D002503:Centromere / Q000276:immunology; D041321:Chromosomes, Human, X; D041322:Chromosomes, Human, Y; D004268:DNA-Binding Proteins; D005819:Genetic Markers; D006801:Humans; D007248:Infertility, Male / Q000235:genetics*; D008297:Male; D008540:Meiosis; D000070957:MutL Protein Homolog 1; D009363:Neoplasm Proteins / Q000235:genetics* / Q000276:immunology; D009687:Nuclear Proteins / Q000235:genetics* / Q000276:immunology; D010749:Phosphoprotein Phosphatases / Q000276:immunology; D011995:Recombination, Genetic; D013090:Spermatocytes / Q000166:cytology / Q000502:physiology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000906:Antibodies; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D005819:Genetic Markers; C501486:MLH1 protein, human; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; C490060:SYCP3 protein, human; C413483:CTDSP1 protein, human; D010749:Phosphoprotein Phosphatases; D000070957:MutL Protein Homolog 1