Opinion ID: 2161593
Heading Depth: 2
Heading Rank: 3

Heading: In vitro studies

Text: Next, Dr. Done turned to the in vitro data on the teratogenicity of Bendectin. He explained that in vitro means in glass, and that in vitro studies are those which are performed in a test tube. Such studies are particularly valuable, he said, because they allow scientists to focus on a specific effect. For example, to determine whether a drug can cause limb-shortening birth defects, limb bud cells of animal embryos (which eventually form the limbs of animals) can be separated from the rest of the embryo, placed in a test tube, and watched to see if their development is thwarted by the drug. Dr. Done relied principally on an in vitro study performed by a Dr. Hassell. In that study Dr. Hassell observed that Bendectin interfered with the growth and development of limb bud cells. This observation led Dr. Done to conclude that the study clearly indicates the potential for teratogenicity is there with regard to limb defects because the focusing that was done in this instance was to focus down on limb bud cells individually and grow them as pure things in culture. When it could be shown that Bendectin interfered with their growth and development, that, of course, indicates that the potential is there. Considering the in vitro evidence in combination with the other data, Dr. Done testified that in his opinion Bendectin caused appellant's birth defects. Here again, Dr. Scott, appellee's expert witness, testified that in vitro studies play a role in the determination of whether a substance is a teratogen. Such evidence, he said, must be considered in light of other available data in reaching an opinion on the teratogenicity of a substance. Dr. Done did not testify otherwise.