Unformatted text preview: into the amniotic sac and fluid is drawn off. Foetal cells, amniocytes, are suspended in the fluid and these can be cultured and their metaphase chromosomes examined. One of the commonest chromosome abnormalities is Down syndrome, the figure links to the relevant passage later in this lecture. • At 9-10 weeks of gestation, it is possible to aspirate via the cervix, a small amount of the placental tissue, the technique of chorionic villus sampling . This tissue can be cultured and chromosomes prepared. • In fertility clinics embryos are often conceived by artificial insemination. A single, totipotent, cell from an 8 cell stage embryo can be examined directly and the information can be used to decide on which embryo to reintroduce into the mother....
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- Fall '10
- Chemistry, Embryo, Chromosome Abnormalities, 10 weeks, 14 weeks