Question

how is dna modified?

Answer 1

DNA the deoxyribonucleic acid is nothing but a group of certain proteins deoxydugars and nitrogen based .. which stores the genetic code .... when it comes to DNA modification it can be of 2 types for the betterment of human life or for harm .
First is the mutation during gamete formation it changes a certain base pair be it deletion , alternation mutations are mostly fatal
Second type of DNA modification is by genetic engineering , to obtain a better variety of product from a certain pair of desirable genes.

Answer 2

DNA is a nucleic acid or a hereditary unit. it's full from is deoxy ribo nucleic acid. it is modified genetically by various genetic engineering techniques. Genetic engineering means direct manipulation of DNA to alter an organism’s characteristics in a particular way.the organism so obtained is called GMO. genetically modified organism. The first genetically modified organism was a bacterium which was created in 1973.

Alteration of DNA is done by various process

☆A small piece of DNA is extracted from the bacteria.
☆ A small section is then cut out of the the extracted DNA by restriction enzymes or also known as  ‘molecular scissors’.
☆ The generic a sequence of DNA for human insulin is inserted into the gap in the that circular cut of DNA. ☆This extracted DNA is now genetically modified or you call it Recombinant DNA.
☆ This genetically modified DNA or also called plasmid is injected into a new bacteria.

hope it helped you