Sex chromosome aneuploidy in sperm-derived pronuclei, motile sperm and unselected sperm, scored by three-color FISH

• Published in: Cytogenetic and genome research Vol. 78; no. 1; pp. 27 - 30
• Main Authors: Martínez-Pasarell, O, Vidal, F, Colls, P, Nogués, C, Egozcue, J, Templado, C
• Format: Journal Article
• Language: English
• Published: Switzerland S. Karger AG 1997
• Subjects: Adult; Aneuploidy; Cell Nucleus - genetics; Color; Humans; In Situ Hybridization, Fluorescence - methods; Male; Sperm Motility - genetics; Spermatozoa - physiology; X Chromosome; Y Chromosome
• ISSN: 0301-0171; 1424-8581; 1424-859X
• DOI: 10.1159/000134620

Aneuploidy is the most common chromosomal abnormality in humans. The paternal origin of aneuploidy accounts for about 5% of 47,XXX, 50% of 47,XXY, 80% of 45,X0 and 100% of 47,XYY. Frequencies of paternal nondisjunction have been reported in human sperm metaphases. Using this approach, it is possible to detect nondisjunction of all chromosomes in human sperm able to fertilize zona-free hamster oocytes and to produce a pronucleus (potentially fertile human spermatozoa). However, this is a difficult technique and frequencies of non-disjunction have been calculated from a low total number of sperm and from a low number of sperm per donor. The introduction of three-color fluorescent in situ hybridization (FISH) allows to screen for sex chromosome aneuploidies in a large number of unselected sperm. Recently, we have developed a method to obtain human sperm-derived pronuclei using the hamster-human system. This method allows the study of aneuploidy in sperm-derived pronuclei by multicolor FISH, increasing the efficiency of the hamster-human fusion technique. Theoretically, potentially fertile sperm and selected motile sperm should better reflect in vivo fertilization conditions than unselected sperm. Previous studies of sperm metaphases or two-color FISH in decondensed sperm did not show differences in the incidence of sex chromosome abnormalities between motile and unselected sperm. However, Templado et al. described significant differences between the incidence of sex chromosome hyperhaploidy sperm complements and that obtained by three-color FISH in sperm nuclei. To avoid interindividual variations and differences in scoring criteria, we have compared the incidence of sex chromosome aneuploidies in 4,901 human sperm pronuclei, 20,570 selected motile sperm and 19,925 unselected sperm nuclei from the same donor by three-color FISH.