Lack of intraindividual variation of unbalanced spermatozoa frequencies from a 46,XY,t(9;22)(q21;q11.2) carrier: case report.
The meiotic segregation pattern of 83 men carrying a balanced reciprocal translocation between two autosomes has already been published. Nevertheless, the question of intraindividual variations has not been addressed yet. A 32-year-old patient was found to be a carrier of a t(9;22)(q21;q11.2) during the investigations for a couple with infertility for 3 years. Two sperm samples were obtained at more than 3 months interval. Both sperm samples were analyzed in triple FISH with the D9Z1 and LSI BCR/ABL ES translocation probes. The frequency of gametes exhibiting a chromosomal imbalance was 45.32% and 42.1% in samples 1 and 2, respectively, with the unbalanced spermatozoa resulting from adjacent 1, adjacent 2, and 3:1 segregation in decreasing frequencies. No statistically significant difference was found between both segregation profiles. Four studies have analyzed the meiotic segregation pattern of translocations within families; they found similar profiles of meiotic segregation in each family, but not between families. This suggests, along with our results, that meiotic segregation is not a random process. More studies on intraindividual variations are necessary to allow a better understanding of the meiotic behaviour of chromosomal rearrangements and the practical interest of studies of this kind.
Morel
F
F
Service de Cytogénétique, Cytologie et Biologie de la Reproduction, CHU Morvan, Brest, Laboratoire d'Histologie, Embryologie et Cytogénétique, Faculté de Médecine et des Sciences de la Santé, Université de Bretagne Occidentale, Brest, France.
Douet-Guilbert
N
N
Le Bris
M-J
MJ
Herry
A
A
Marchetti
C
C
Lefebvre
V
V
Delobel
B
B
Amice
V
V
Amice
J
J
De Braekeleer
M
M
D000328:Adult; D002869:Chromosome Aberrations; D020090:Chromosome Segregation; D002892:Chromosomes, Human, Pair 22; D002899:Chromosomes, Human, Pair 9; D041321:Chromosomes, Human, X; D041322:Chromosomes, Human, Y; D005787:Gene Frequency; D006579:Heterozygote; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008540:Meiosis; D009845:Oligospermia / Q000235:genetics* / Q000473:pathology*; D014178:Translocation, Genetic