Direct analysis of the chromosome constitution of human spermatozoa

摘要: ALL available information on the chromosome constitution of human gametes is speculative, having been obtained by inference from conceptuses that survive sufficiently long to produce a clinically recognisable pregnancy. A minimum 10% all recognised conceptions are chromosomally abnormal, and it has estimated 1–2% result fertilisation spermatozoon with abnormality1. Cytological evaluation spermatozoa restricted staining fixed smears whole sperm2–13. Certain regions peculiar properties, such as arm Y heterochromatic region 9, presumed be represented in appropriately stained sperm nuclei differentially spots. By counting number these spots per nucleus, frequency aneuploidy normal males around 40% (refs 5, 9–11). The precision data dubious, because several factors must taken into consideration when blobs counted head nuclei, which could contribute biased estimates nondisjunction7,8,12. For this reason, some claims have now retracted12,13. To investigate true contribution male production abnormal influencing survival sperm, necessary analyse chromosomes directly. However, after meiotic metaphase II do not reappear until female pronuclei fertilised egg prepare for first cleavage division. We report here use hamster eggs activate point where their can studied