And DNA

Today we will be talking about a very fascinating topic: DNA. This molecule are found in the heart of our cells; the nucleus. In there, these molecules code for proteins, which are very important for our body. These proteins act like hormones and, muscle tissues, enzymes and many other important things, making us what we are. We can either make DNA in our cells, or we can obtain by digesting other organism such as animals and plants. Now, let us dig deeper into the mysteries of the DNA.

Its structure and how the bases pair

The DNA is shaped like a double helix. The double helix is formed by two strands (made out of phosphates and sugar. The strands are connected together by bases, which always pair up in the same way because of the complementary (matching) shape of molecules. Adenine (A) pairs up with Thymine(T) and cytosine(C) pair up with guanine(G). The matching bases are known as complementary bases pairs. They are joined together by a weak hydrogen bond. The order of these complementary bases in DNA contains information needed to for proteins for body cells. We each have a slightly different order of bases in our genes and this make us slightly different (aka variation in species). This is why even though our genes are so similar, we all look different because of these small differences in DNA sequencing.
Here is diagram depicting the structure of DNA:

How was DNA discovered?

The first major event that was part of the discovery of DNA was in the 1950s, King College London. Maurice WIlkins (1916-2004) and Rosalind Franklin(1920-1958) were studying the structure of DNA using X-rays. Franklin directed beams of X-rays at purified DNA and used photos to record how the molecules of DNA scattered the X-tays. When they analysed the pattern, they were able to understand a bit about the structure of DNA.

Meanwhile in Cambridge University, Francis Crick (1916-2004) and James Watson(1928-) were trying to build a 3D model of the DNA structure (human size of course). Maurice Wilkins, without the permission of Franklin, showed some their X-ray photographs, which the two men at cambridge used to perfect their model.The two men only noted the London group in the footnote. In 1962, James Watson and Francis Crick, along with Maurice Wilkins, were awarded a nobel prize for their discovery. However, Franklin didn’t receive the price because because she has died 4 years ago. The discovery of DNA led to the formation of a project called Human Genome Project (HGP)

What was the Human Genome Project (HGP)?

The Human Genome Project (HGP) was an international effort that involved scientist working in 18 different countries and sharing data they collected using the latest developments in technology to help them.

Finally, in 2003, after 13 years of hard work, the HGP was complete!!! Uptil now, scientists has successfully completed sequence (order) of 3 billion base pairs that make up the human genome(all the genes of an individual). Although each human being has a unique DNA sequence, the project shows that everyone has at least 99.9% of their DNA common.

The potential use of HGP?

• We could use the results HGP has provided us with by using them to:
• It can improve the method used in testing for genetic disorder (to discover if people are carrying faulty genes) we can invent new ways for finding genes that may increase the chance for having diseases such as Alzheimer new treatment and cures for disorders e.g. gene gene therapy. Scientists are trying to replace or mend faulty genes that cause disorders 
• The results can give us new of seeing the changes of genome over time. Maybe we could track evolution of species to see what conditions cause variations to triumph (survival of the fittest)? 
• By using someone’s genome, we could make personalised medicine - this may make disease be more effective at targeting diseases