When the CAU anticodon of a tRNAMet was modified to UAC, the anticodon for tRNAVal, valine aminoacyl-tRNA synthetase, recognized the altered tRNAMet and added valine rather than methionine to it. When the converse modification was made, the altered tRNAValcontaining a CAU anticodon (rather than UAC) was recognized and activated by methionine aminoacyl-tRNA synthetase. What do these data suggest about the mechanism by which aminoacyl-tRNA synthetases recognize their cognate tRNAs

With the information obtained, it can be deduced that the tRNA anticodon region is recognized by an aminoacyl-tRNA synthetase, however some of these enzymes may have different elements in their structure and which would be the majority and which may trigger a fundamental role in the aminoacyl-tRNA synthetase recognition

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."