Two possible threats emerge in separate reports from the United Kingdom. Because it takes place at the submicroscopic level, it's impossible to see if a gene splice is successful. You then know that whichever cells survive have incorporated the transgene with its accompanying marker. When genetically modified seeds are planted in fields, the marker gene will still be in every cell of the growing plant. This is not a good idea at a time when doctors are finding a growing number of disease strains, including tuberculosis bacteria, that are resistant to all known antibiotics.
Recent publications show that pathogenic bacteria can carry transgenic DNA into mammalian cells.
MAFF used the example of the ampicillin resistance marker gene, which deactivates penicillin and similar antibiotics. However, it is highly mutable and so could be reactivated in bacteria and possibly become resistant to a wider spectrum of antibiotics. The second development was reported by Dr. Mae-Wan Ho of the biology department of the Open University in a letter to the British Society of Plant Breeders dated July 13, 1999. Foreign genes won't work unless accompanied by a genetic promoter that the host cell will respond to and activate the new gene. Viruses are strands of DNA or RNA with a protein coat.