Abstract: BACKGROUND ＆ AIM: The purpose of this paper was to develop a method of multi－color FISH which could be used to detect the frequencies of numerical and structural chromosomal aberrations in sperm simultaneously. MATERIAL AND METHODS:Two probes for chromosome 1(one for centromere labeled with biotin，the other for terminal of short arm labeled with digoxingenin)and two probes for centromere chromosome 18 labeled with biotin or digoxingenin. The hybridization signals were detected with CY3－strepavidin for botin－labeled probes，and anti－digoxingenin antibodies conjugated with FITC for digoxingenin probes. RESULTS: Under the blue fluorescenses background ，three hybridized signals red ， green ， and yellow , were clearly visible in the sperm nucleus . The red signals represented the target of chromosome 1 ; green signals represented the target of chromosome 1p terminal， and yellow signals (which was the mixed color of red and green) represented the centromere of chromosome 18. 　　Three kinds of chromosomal abnormalities were simultaneously detected by the multi－color FISH: the frequencies of disomic and nullisomic sperm for chromosome 1 and 18;the frequencies of duplication and deletion of cetromere ， telemere for chromosome 1; and the frequency of diploidy sperms. 　　A total of 135 937 sperm nucleus of 14 normal health men were counted. The frequencies of numerical and structural aberrations were detected. The frequencies of disomic and nullisomic were 0.045 ％ and 0.048 ％ for chromosome 1，0.053 ％ and 0.045 ％ for chromosome 18， respectively; the frequencies of duplication and deletion for 1p terminal were 0.082 ％ and 0.069 ％ respectively; the frequencies of duplication and deletions for chromosome 1 centromere were 0.075 ％ and 0.06 0 ％ respectively; and the frequencies of diploidy sperm was 0.061 ％. All the values detected were in the range of the data published in literature . CONCLUSION: Multi－color FISH could be used to detect the numerical and structural chromosome aberrations of sperm in normal men and exposed to environmental chemicals.

Key words: Multi－color fluorescence in situ hybridization, sperm, chromosome structural aberrations, aneuploidy