Analysis of segregation in a human male reciprocal translocation carrier, t(1;11) (p36.3;q13.1) by two‐colour fluorescence in situ hybridization

Abstract

Using centromeric probes specific for chromosomes 1 and 11, 13,071 sperm nuclei from a male reciprocal translocation heterozygote, 46,XY,t(1;11) (p36.3;q13.1), were analyzed by fluorescence in situ hybridization (FISH). Decondensed sperm nuclei were simultaneously hybridized with DNA probes for chromosome 1 (pUC177) and chromosome 11 (D11Z1). Results were as follows: 1/11 (82.45%), 1/1/- (3.45%), -/11/11 (4.85%), 1/1/11 (1.20%), 1/11/11 (1.14%), 1/- (4.33%), -/11 (2.50%), 1/1/11/11 (0.06%), 1/1/1/- (0.02%). Because both the normal chromosome and its translocated derivative carry the same centromeric sequences, FISH cannot differentiate between sperm resulting from alternate segregation and those produced by adjacent I segregation. Using the same donor, comparable segregation patterns were obtained from sperm chromosome karyotypes (Spriggs et al., 1992: Hum Genet 88:447-452) and from MII spermatocytes (Goldman and Hulten, 1993: Cytogenet Cell Genet 63:16-23), demonstrating that selection is not a factor in the human sperm/hamster oocyte fusion technique or during meiosis. Although FISH does not provide the detailed information afforded by sperm karyotyping, it is a valuable technique for studying segregation patterns in translocation heterozygotes.

Meiotic segregation analysis in a t(4;8) carrier: comparison of FISH methods on sperm chromosome metaphases and interphase sperm nuclei

“…Although statistical differences were found in the FISH system, no significant differences between 22,N and 24,N chromosomes were observed in the human ± hamster analysis (w 2 test, P=0.4156). The excess of 3 : 1 hypohaploidies over 3 : 1 hyperhaploidies has also been observed in other twocolour FISH 26 and three-colour FISH studies. 28 Other works 22,29 indicated that technical artefacts could explain these apparent discrepancies: the sperm head is small, and as a result the number of probes that can be individually scored is limited.…”

“…(2) FISH on sperm nuclei has higher statistical resolution than sperm chromosome complement analysis (6524 sperm nuclei versus 352 chromosome complements). However, it is important to point out that the number of chromosome complements analysed by previous comparative studies 13,26,27 ranged from 72 to 542, and no significant differences between both types of analysis were found. (3) Technical limitations of both analysis.…”

“…Spriggs et al 26 and Estop et al 27 have compared the results of chromosome segregation into sperm nuclei by double-FISH and the results of sperm cytogenetic studies using the hamster system. Besides, Estop et al, 13 have reported a comparison of triple-FISH on sperm nuclei and results on sperm chromosome complements.…”

“…A selection not directly based on the chromosomal content but on motility, carried out after a 1-h swim-up could act on sperm that, for some reason, have a reduced motility. However, since the results of Spriggs et al 26 and Estop et al 27 suggest that there is no sperm selection based on chromosome content, more comparative studies must be performed in order to settle this phenomenon. (2) FISH on sperm nuclei has higher statistical resolution than sperm chromosome complement analysis (6524 sperm nuclei versus 352 chromosome complements).…”

Fluorescence in situ hybridisation (FISH) analysis of chromosome segregation and interchromosomal effect in spermatozoa of a reciprocal translocation t(9,10)(q11;p11.1) carrier

“…Sperm karyotypes are able to evaluate separately the result of the different segregation modes. FISH studies in dual colour, using in most cases centromeric probes for the chromosomes involved in the translocation, do not allow to differentiate alternate and adjacent-1 segregants (Spriggs and Martin 1994;Rousseaux et al 1995;Mennicke et al 1997;Estop et al 1997;Mercier et al 1998;Giltay et al 1999). One exception was the translocation (7;8)(q11;q21;cen) reported by Mercier et al (1998).…”