title: The effects of age and abnormal sperm count on the nondisjunction of spermatozoa.
abstract: OBJECTIVE
  The effect of paternal age on the nondisjunction of sex chromosomes is controversial. Also, the prevalence of chromosomal anomalies in infertile patients is controversial, it has been reported that the sex chromosomal aneuploidy rate following treatment with intracytoplasmic sperm injection (ICSI) is higher than in naturally conceived pregnancies. We investigated the influence of paternal age and oligozoospermia on the nondisjunction of spermatozoa.
  
  
  METHODS
  We determined the rate of aneuploidy for gonosomes and autosomes, using two-color fluorescence in situ hybridization (FISH) of the X and Y chromosomes and chromosomes 12 and 18 in 10 donors under 25 years of age who had a normal sperm count (> or = 20 x 10(6)/ml), 10 donors over the age of 39 years with idiopathic infertility and normozoospermia (> or = 20 x 10(6)/ml), and 5 oligozoospermic donors (< 20 x 10(6)/ml).
  
  
  RESULTS
  There was no obvious relationship between increasing age and autosomal disomy (disomy 12 and disomy 18). Neither autosomal disomy nor diploidy was increased in any group. The frequency of X-, Y-, XX-, and YY-bearing sperm did not differ significantly among groups, but the frequency of XY-bearing sperm was significantly higher in the older infertile group than in the control donors.
  
  
  CONCLUSIONS
  The incidence of nondisjunction of paternal sex chromosome in meiosis I was higher in older men with idiopathic infertility. The present results suggest that the risk of producing XXY fetuses is higher among men > 39 years of age with idiopathic infertility.
authors.affiliation: Department of Obstetrics & Gynecology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Asada
authors.forename: K
authors.initials: K
authors.lastname: Sueoka
authors.forename: T
authors.initials: T
authors.lastname: Hashiba
authors.forename: M
authors.initials: M
authors.lastname: Kuroshima
authors.forename: N
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshimura
mesh_terms: D000328:Adult; D000367:Age Factors; D000782:Aneuploidy; D002869:Chromosome Aberrations; D002881:Chromosomes, Human, Pair 12; D002887:Chromosomes, Human, Pair 18; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007248:Infertility, Male / Q000235:genetics*; D008297:Male; D008540:Meiosis; D009845:Oligospermia / Q000235:genetics / Q000473:pathology; D013076:Sperm Count; D013094:Spermatozoa / Q000502:physiology*; D014960:X Chromosome; D014998:Y Chromosome