What is dehydration synthesis in detail?

Dehydration Synthesis Definition

Dehydration synthesis refers to the formation of larger molecules from smaller reactants, accompanied by the loss of a water molecule. Many reactions involving dehydration synthesis are associated with the formation of biological polymers where the addition of each monomer is accompanied by the elimination of one molecule of water.

Dehydration reactions are a subset of condensation reactions where two functional groups combine to form a covalent bond along with the release of a small molecule such as water, HCl, methanol or acetic acid. Though all these small molecules are frequently seen in large-scale industrial synthesis of organic molecules, in biological systems, water is the most frequent byproduct of a condensation reaction.

it would affect precipitation by causing flooding in some areas of the world due to climate increasing, causing the glaciers in the northern and southern pole of our planet to melt.

i wish you would have provided choices to simplify it and allow me to give an exact answer.

"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."