Michael C. Summers

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The addition of amino acids to a modified simplex optimized medium (mKSOM) did not increase the percentage of blastocysts that develop from CF1 mouse ova fertilized in vitro. In contrast, the percentage of blastocysts that began to hatch and the number of cells in these blastocysts, particularly in the inner cell mass, was increased. The added amino acids(More)
Crossover recombination reshuffles genes and prevents errors in segregation that lead to extra or missing chromosomes (aneuploidy) in human eggs, a major cause of pregnancy failure and congenital disorders. Here we generate genome-wide maps of crossovers and chromosome segregation patterns by recovering all three products of single female meioses.(More)
A new medium derived from the use of sequential simplex optimization methods (SOM) that overcomes the block to development beyond two cells in vitro in embryos of the CF1-cultured strain of mouse has recently been described. Contrary to previous reports, glucose was shown to have no significant inhibiting effect on embryo development to the blastocyst stage(More)
Considerable advances in media development for the culture of preimplantation mammalian embryos have been made since mouse embryos were first cultured and successfully transferred to foster mothers. The purpose of this review is to detail the history of the development of chemically defined media for the culture of preimplantation embryos. Two approaches(More)
A review of the literature shows divergent differences between laboratories of the effects of glutamine in mouse preimplantation embryo culture media. One laboratory reported several cases of exencephaly, which was attributed to ammonia produced by the breakdown of glutamine. Two other laboratories have found no such effects. It is suggested, but not(More)
A comparison was made of the development of human zygotes in either a one-step (Global® medium) or two-step culture system (Quinn's Advantage®). A total of 257 normally fertilized 2PN zygotes from 28 patients were used in the study. The study was broken down into two parts: the first concerned the development of embryos from Days 1 to 3 in Global® medium(More)
The effect of replacing bovine serum albumin (BSA) in a simple defined medium (KSOM) with polyvinyl alcohol (PVA) and/or amino acids on the percentages of mouse zygotes that develop to at least the blastocyst stage and that hatch at least partially or completely is reported. Blastocysts could form when BSA was replaced with only PVA, but at a moderately(More)
Preimplantation genetic diagnosis (PGD) for monogenic disorders has the drawback of time and cost associated with tailoring a specific test for each couple, disorder, or both. The inability of any single assay to detect the monogenic disorder in question and simultaneously the chromosomal complement of the embryo also limits its application as separate(More)
The advice that should be given to a couple considering assisted reproductive technologies for the treatment of their infertility, when they are completely opposed to the destruction of surplus embryos, is discussed. It is urged that they do not use treatments that generate surplus embryos. They should be given the options of declining IVF and considering(More)
BACKGROUND The development of the mouse zygote following fertilization in vitro in a KSOM-type medium containing either L-glutamine or glycyl-L-glutamine has been examined, and compared with the development of mouse zygotes produced by natural fertilization. METHODS Mouse IVF, embryo culture and embryo transfer. RESULTS Fertilization rates, development(More)