DNA synthesis is actually the process of making new deoxyribose nucleic acid (DNA). It is catalyzed by the polymerase enzyme.

Latest researches have been working on genome sequencing and synthesis. In 2003 the human genome was completed. In DNA synthesis, the nucleotide are reassembled in a sequence that is required by the particular genomic matter. The correct sequence of nucleotides are added by DNA synthesizers, it also allows acting on such information to deliver the synthesized DNA.

Both in vivo and in vitro process of DNA synthesis are defined in this article.

In in-vivo DNA syntheses, DNA is copied by the replication process and is transferred I, the same form to the daughter cell. New DNA is synthesized in a replication process. Polymerase plays an important role in this process. The polymerase is an enzyme and it catalysis the synthesis reaction. DNA is made up of nucleotide that are sugar, phosphate and bases.

In the in vitro synthesis, the process of the synthesis occurs outside the body. The process of in vitro synthesis is called amplification as it is done by temperature, instead of enzymes.

The sequence of the nucleotide bases that are As, Ts, Cs, Gs in a DNA are determined by the process called DNA sequencing. With the correct use of equipment and materials, It is easier to sequence a short piece of DNA. Sequencing an entire genome, which includes the DNA of all the organisms, remains a difficult task.

It needs the breakage of the DNA of the genome into many smaller pieces, sequencing the pieces, and assembling those sequences into a single long “consensus.” But the methods that are new and have been developed over the past two decades, genome sequencing is now much faster and non-expensive than it was at the time of the Human Genome Project.

Followings are the most useful methods of DNA sequencing.

  1. Sanger’s Method
  2. Maxam and Gilbert Method
  3. Hybridization Method
  4. Pal Nyren’s Method
  5. Automatic DNA Sequencer
  6. Slab Gel Sequencing Systems
  7. Capillary Gel Electrophoresis

In the beginning of late 1990s, scientific community observed an exceptional climax of accomplishments related to DNA sequencing. The sequences have been generated for the genomes of several key model organisms, with the historic sequencing of the human genome. More developments are being made in DNA sequencing.

This article is jointly written by Syeda Moazzama Razavi And Zeinab Jamal, Genetics Department, Kinnaird College For Women University, Lahore