When a phosphate group is removed from the molecule
When was BSE first discovered?
BSE first appeared in British cattle in the mid-1980s. There have been numerous cases detected in other countries. A complete list of countries is available from both the U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA).
Answer:
A) A transgene integrated into a heterochromatic region of the genome.
Explanation:
This is most likely the reason why the transgene is not expressed in the fifth cell line. It is likely that the transgene was integrated into a heterochromatic region of the genome. Heterochromatin consists of genetically inactive satellite sequences, and many of these are repressed to various extents. Moreover, because this is a tightly packed form of DNA or condensed DNA, it is inaccesible to polymerases and thus not transcribed.