title: Sperm fluorescence in situ hybridization study in nine men carrying a Robertsonian or a reciprocal translocation: relationship between segregation modes and high-magnification sperm morphology examination.
abstract: OBJECTIVE
  To evaluate whether observation of spermatozoa at × 6,100 magnification can distinguish between those with and without a balanced chromosomal content.
  
  
  METHODS
  Retrospective research study.
  
  
  METHODS
  Genetics laboratory of a university hospital and in vitro fertilization center.
  
  
  METHODS
  Six men carrying a reciprocal translocation and three men with a Robertsonian translocation.
  
  
  METHODS
  Sperm fluorescence in situ hybridization (FISH) with a specific set of three probes for each translocation for determining chromosomal content, performed on both unselected spermatozoa and on spermatozoa selected at × 6,100 magnification according to the Cassuto-Barak classification.
  
  
  METHODS
  Chromosomal content in unselected and selected spermatozoa.
  
  
  RESULTS
  Chromosomal translocations lead to gametes carrying either a balanced or an unbalanced karyotype in offspring and consequently to changes in chromosome position within sperm nucleus and potentially in nuclear morphology. In the unselected spermatozoa, the rate of chromosomally balanced nuclei ranged from 37.1% to 52.6% and from 70% to 88.6% in reciprocal and Robertsonian translocations, respectively, which is in agreement with published data. In selected spermatozoa, there was no statistically significant difference between the rates of segregation modes when compared with their frequencies in unselected sperm cells.
  
  
  CONCLUSIONS
  The observation of spermatozoa at high-magnification in translocation carriers cannot be used to select sperm cells with a balanced chromosomal content.
authors.affiliation: ART Unit, Drouot Laboratory, Paris, France.
authors.forename: Nino Guy
authors.initials: NG
authors.lastname: Cassuto
authors.forename: Nathalie
authors.initials: N
authors.lastname: Le Foll
authors.forename: Sandra
authors.initials: S
authors.lastname: Chantot-Bastaraud
authors.forename: Richard
authors.initials: R
authors.lastname: Balet
authors.forename: Dominique
authors.initials: D
authors.lastname: Bouret
authors.forename: Alexandre
authors.initials: A
authors.lastname: Rouen
authors.forename: Rakia
authors.initials: R
authors.lastname: Bhouri
authors.forename: Capucine
authors.initials: C
authors.lastname: Hyon
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Siffroi
mesh_terms: D000328:Adult; D020090:Chromosome Segregation / Q000235:genetics*; D006580:Genetic Carrier Screening / Q000379:methods; D006579:Heterozygote; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D007248:Infertility, Male / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D012189:Retrospective Studies; D013094:Spermatozoa / Q000737:chemistry / Q000502:physiology*; D014178:Translocation, Genetic / Q000235:genetics*