Munné S, Sultan K M, Weier H U, Grifo J A, Cohen J, Rosenwaks Z
Center for Reproductive Medicine and Infertility, New York Hospital-Cornell Medical Center, NY 10021, USA.
Am J Obstet Gynecol. 1995 Apr;172(4 Pt 1):1191-9; discussion 1199-201. doi: 10.1016/0002-9378(95)91479-x.
Our purpose was to determine the feasibility of ascertaining aneuploidy for chromosomes X, Y, 18, and 16 by use of multiple-probe fluorescence in situ hybridization in blastomeres from preimplantation human embryos.
A short fluorescence in situ hybridization procedure involving the simultaneous use of four deoxyribonucleic acid probes detected with red, green, blue, or a mixture of red and green fluorochromes was developed to determine numeric abnormalities of chromosomes X, Y, 18, and 16. Embryos underwent biopsy, and all or most cells were analyzed to distinguish true aneuploidy from mosaicism and to assess technique variations within the same embryo (n = 64).
The analysis of all the blastomeres of an embryo was achieved in 91% of the embryos. Successful analyses including biopsy, fixation, and fluorescence in situ hybridization were achieved in 87.8% of the blastomeres. Of the four chromosomes tested, numeric aberrations were found in 23% and 42% of normally and abnormally developing embryos, respectively, including aneuploidy, polyploidy, haploidy, and mosaicism. When diploid embryos containing one or several tetraploid cells are counted as chromosomally abnormal, then 49% and 61% of normally and abnormally developing embryos, respectively, were chromosomally abnormal. Aneuploid embryos consisted of two monosomies for chromosome 16, one for chromosome 18, and a trisomy for chromosome 16. There was a tendency for aneuploidy to increase with maternal age.
Fluorescence in situ hybridization is a more efficient method than cytogenetic analysis to study specific aneuploidies at preimplantation stages of development in human embryos. In addition, the preimplantation genetic diagnosis of two blastomeres per eight-cell embryo may be sufficient to ensure successful analysis of polyploidy, haploidy, and specific aneuploidies without endangering the survival of the embryo. The technique can be easily modified to consider other chromosomes, including 13 and 21. Because most chromosomally abnormal embryos do not develop to term, the use of this technique may increase the delivery rate per embryo by allowing only transfer of embryos normal for the tested chromosomes. This technique would be most useful for older women undergoing in vitro fertilization, because aneuploidy appears to increase with advancing maternal age.
我们的目的是确定通过使用多探针荧光原位杂交技术检测植入前人类胚胎卵裂球中X、Y、18和16号染色体非整倍体的可行性。
开发了一种短荧光原位杂交程序，该程序同时使用四种用红色、绿色、蓝色或红色与绿色荧光染料混合物检测的脱氧核糖核酸探针，以确定X、Y、18和16号染色体的数目异常。对胚胎进行活检，并分析所有或大多数细胞，以区分真正的非整倍体与嵌合体，并评估同一胚胎内的技术差异（n = 64）。
91%的胚胎实现了对其所有卵裂球的分析。包括活检、固定和荧光原位杂交在内的成功分析在87.8%的卵裂球中得以实现。在所检测的四条染色体中，正常发育和异常发育胚胎中分别有23%和42%发现了数目畸变，包括非整倍体、多倍体、单倍体和嵌合体。当将含有一个或几个四倍体细胞的二倍体胚胎视为染色体异常时，正常发育和异常发育胚胎中分别有49%和61%为染色体异常。非整倍体胚胎包括两条16号染色体单体、一条18号染色体单体和一条16号染色体三体。非整倍体有随母亲年龄增加而增多的趋势。
荧光原位杂交是一种比细胞遗传学分析更有效的方法，用于研究人类胚胎植入前发育阶段的特定非整倍体。此外，对每个八细胞胚胎的两个卵裂球进行植入前基因诊断可能足以确保对多倍体、单倍体和特定非整倍体进行成功分析，而不会危及胚胎的存活。该技术可以很容易地进行修改以检测其他染色体，包括13号和21号染色体。由于大多数染色体异常的胚胎无法发育至足月，使用该技术仅允许移植所检测染色体正常的胚胎，可能会提高每个胚胎的分娩率。该技术对接受体外受精的老年女性最为有用，因为非整倍体似乎会随着母亲年龄的增加而增多。
