Non-disjunction in human sperm: results of fluorescence in situ hybridization studies using two and three probes

Abstract

Fluorescence in situ hybridization using two or three probes was utilized to estimate the incidence of diploidy, the incidence of disomy for the sex chromosomes and chromosomes 16 and 18, and the proportion of Y- and X-chromosome bearing sperm, in a series of normal males. Our results demonstrate the importance of using an approach capable of distinguishing disomy from diploidy, as most donors had levels of diploidy higher than the disomy levels of individual chromosomes. Our analyses suggest the existence of chromosome-specific mechanisms of paternal non-disjunction, as sex chromosome disomy was approximately 1.5 times as common as disomy 16, and over two times as common as disomy 18. In studies of gametic sex ratio, we found little evidence for marked deviation from an expected 1:1 ratio.

Detection of aneuploidy in human spermatozoa using fluorescencein situ hybridization (FISH)

“…The disomy rate (0.39%) for chromosome 17 in this study is comparable to those (0.33% and 0.31%) by Han et al (1992) and by Guttenbach et aL (1994a), while higher than that (0.13%) in the report of Bischoff et al (1994) (Table 5). The disomy rate (0.33%) obtained for chromosome 18 is comparable to those (0.36% and 0.25%) by Guttenbach et al (1994b) and by Bischoff et aL (1994), while higher than that Williams et al (1993) and by Griffin et al (1995) (Table 5). On the contrary, the diploidy rate in this study is comparable to those of other investigators (Han et al, 1992;Williams et aL, 1993;Miharu et aL, i994) (Table 5).…”

“…The disomy rate (0.33%) obtained for chromosome 18 is comparable to those (0.36% and 0.25%) by Guttenbach et al (1994b) and by Bischoff et aL (1994), while higher than that Williams et al (1993) and by Griffin et al (1995) (Table 5). On the contrary, the diploidy rate in this study is comparable to those of other investigators (Han et al, 1992;Williams et aL, 1993;Miharu et aL, i994) (Table 5). The discrepancies in the disomy rates among investigators may have been due to different sample sizes and different scoring criteria of disomic sperm.…”

“…Lower hybridization efficiencies tended to result in under-estimation of disomy or diploidy rates. Our pretreatment method of sperm with DTT is simple and easy, compared with other protocols (Robbins et aL, 1993;Holmes and Martin, 1993;Han et aL, 1992;Williams et al, 1993). Previous investigators used DTT for longer treatment time and sometimes required subsequent treatment with a lithium salt.…”

“…The rates of XX-and YY-diploid sperm are needed to calculate the true rates of disomy for sex chromosomes. Williams et aL (1993) reported that about 75% of diploid sperm were produced in meiosis II error. Using this datum, mean frequencies of XX-and YY-sperm in this study are calculated to be 0.18% and 0.15%, respectively.…”

“…We could not find any differences in the disomy rates among the different autosomes studied in this paper (p=0.748). Although Williams et al (1993) reported a significant increase of the XY-sperm rate by FISH experiments as well as karyotyping, no study on the comparison of the disomy rates among all chromosomes has yet been reported. Thus, further studies are also needed.…”