What is DNA?

DNA stands for deoxyribonucleic acid. It is a major component of a molecular unit called a 'Nucleotide' which is the building block of biological life.

These nucleotides come in 4 forms, depending on which nitrogen 'base' is attached to it. Billions of these nucleotides are bound to each other like a string to form a 'genome'. The fascinating aspect of DNA is that each of these nucleotides is bound to another nucleotide laterally to form a 'base pair', what is called 'complementary binding', and the shape that these base pairs take up is what is referred to as the DNA 'Double Helix' superstructure.

Read more

What is a Genome?

The human genome contains 3.2 Billion base pairs, the exact sequence of which varies from person to person. Most of the trillion cells in a human being have a 'nucleus' that harbours an individual's DNA inside. Hypothetically, if a human being is a Building, DNA is the biological equivalent of the blueprints for that building. i.e. DNA contains all the information required for the construction of a human being.

This blueprint is responsible for the synthesis of all protein components in the body, and as such, contains the genetic data for reproduction of life. Every different type of cell in a biological organism contains all the genetic data needed for its replication, that is, each cell is capable of reproducing itself when it is necessary.

During conception, maternal and paternal DNA is combined to create a new genome that is inherited by their child, and in doing so they are 'passing on' their genetic material to a new generation, this is why children look, and sometimes act like their parents, because they share much of the same genetic material and thus express many similar physiological traits.

What do the lines in a GenePortrait represent?

A GenePortrait is digital image of your unique 'genetic band pattern' after it has run through an Agarose gel.

The science behind the bands:

1. When you give us a sample of your cheek cells, several thousand free buccal cells will be deposited onto the cheek swab. The cheek swab sample will yield between 500-2000ng of DNA.
2. Firstly, the DNA is extracted from all the cells on the cheek swab using a sequence of lysis buffers and centrifugation.
3. Once all DNA from the cells is extracted, this 'mass' of DNA will still be barely visible with the naked eye.
4. So what we have to do is 'amplify' this quantity of DNA to make it visible and workable.
5. This is done using a method called Polymerase Chain Reaction, this process involves using special enzymes, buffers and specifically designed 'primers' that amplifies only specific regions of DNA.
6. Once this process is complete, there is then enough DNA to be able to identify regions specific to only you, that is, your genes.
7. The molecular variance of genes is what makes each of us unique.
8. What WE do, is amplify certain regions (fragments) of certain genes that display some of your unique characteristics.
9. Once these regions are amplified we create 'Wells' in an Agarose gel to prime your DNA to be 'loaded' into 6 consecutive inner lanes, the outer two lanes are molecular ladders.
   (Since DNA has an electric charge, and the 'Charge' of a particular fragment of DNA is directly proportional to its length i.e. its molecular weight)
10. Once the wells are 'loaded' with your DNA, a voltage is applied to the whole gel and the 'Fragments' of DNA (of varying sizes) migrate through the gel at speeds proportional to their size.
    (The bands are hindered by the gel matrix in direct proportion to their size (i.e. the smaller fragments migrate faster and the larger fragments migrate slower)
11. Eventually the varying fragments migrate sufficiently throughout the gel and create a 'Band Pattern' in the gel. This Pattern is unique to every person, as mentioned before this is because we amplified regions of genes that are unique to everyone.
12. The gel is then illuminated under Ultraviolet light (UV) so that the bands shine brightly.
13. Finally, using a special camera, a high resolution digital image is taken of the gel under UV illumination.
14. Et Voila! A snapshot of your DNA has been captured and will be transformed by DNA-DX into a beautiful work of art.

Facts about the DNA and the Human genome:

An analogy to the human genome stored on DNA is that of "Instructions stored in a book":

1. This book would be over 1 billion words long;
2. The book would encompass approximately 5000 volumes, each 300 pages long;
3. The book would fit into a cell 'nucleus' the size of a pinpoint;
4. A copy of the book (all 5000 volumes) would be contained in almost every cell in the human body
5. That's a pretty big book

Top