The news on researching and mapping the human DNA has proven to be quite the monumental task for scientists and researchers. Can you imagine the ability to identify disease now?

The process of human development begins with a male gamete (sperm) able to penetrate the membrane of the female gamete (ovum). They contain more than a billion chemically coded genetic information which together, represent only one half of the blueprint for human development.

The two gametes sit separately together side by side for about an hour or more within the membrane of the ovum, then will suddenly merge, combining their genetic material to form a one cell organism, now called a zygote.

A third process is soon initiated called differentiation during cell division where various cells begin to specialize and reproduce at different rates according to their programmed function to become specific body organs while others will die early or continually reproduce for decades and others, will lie dormant until puberty, adulthood or old age.

Genes are the basic units containing these genetic instructions which are strands of DNA (deoxyribonucleic acid) arranged in particular coded sequences. Every human has forty-six chromosomes in twenty-three pairs each combined and matched from the mother and father forming a new genetic blueprint.

Each DNA strand is shaped in a double helix and resembles a ladder. Each side runs in opposite directions and the rungs are hydrogen-bonded complementary bases. These hydrogen bases are formed and governed by the base pairing rule : A always bonds with T and C always bonds with G. These four bases are two purines, adenine (A), guanine (G) and two pyrimidines, cytosine (C) and thymine (T) .

The Human Genome Project was completed in 2003 by decoding the human genome and identifying these pairs of nucleotides in sequence. All humans may not look or act alike but at the DNA level we are 99.9 % the same.

The scientists were able to discover we have 20-25k different genes, their exact order in the DNA sequence and what normal versions should resemble therefore able to locate disease variants easier and quickly.

Mutations result from copying errors or incorrectly repaired breaks in the DNA molecule which changes the base sequence. These can be passed from parent to child and usually occurs in strands with repetitive pairs vulnerable to copying errors . These breaks can occur from radiation, toxins or not being replicated exactly during cell division.

Geneticists can test and identify for specific gene mutations in unaffected family members with histories of disease and illness to assess risk. Today, people are able to be offered frequent monitoring and preventative measures if they test positive with hereditary diseases.

Difficulty can arise when there are more genes involved but genetic markers (T, C, G, A) help find where the sequence maybe different and serves as a alert that a mutant gene is nearby, termed as single nucleotide polymorphisms, SNP’s (pronounced snips). These snips are taken from people with suspected mutated genes and compared to a normal gene sequence.

Newborn babies can be screened with the use of a $300K machine called tandem mass spectrometers and a drop of blood for early detection of disorders. New discoveries are made and learned to help medical professionals to provide improved care for disease and the map of our own DNA for reference. Read related –> here and there.

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