The genome level of hereditary material organization

The organization of hereditary material presented by nucleic acids and the principles of genetic information coding in prokaryotes and eukaryotes shows the similar origin of them.

The genome - is an assemblage of all haploid chromosome set genes of definite species. The genome level of hereditary material organization has specific features in prokaryotes and eukaryotes.

The virus genomic nucleic acid is consisted of structural genes only. In the bacterial genome most of the genes are unique. That means they are in chromosome only in one copy. Only exclusion is genes, which encode rRNA and tRNA. These genes are repeated in bacterial genome several times. It is interesting to note a discrepancy between nucleotide number and gene number in bacteria genome. It was stated that DNA of E.coli contain 3.8 millions of nucleotide pairs. At the same time, it was found around 1000 structural genes in E.coli. Such genes contain only about 1-1.5 millions of nucleotide pairs.

It is clear that only way is to suggest that the rest of nucleotides are in DNA regions with undiscovered function. The DNA spiralization in prokaryotes is less than in eukaryotes.

The eukaryotes genome has more complicate organization. It contains larger numbers of genes, and larger amounts of DNA in the chromosomes. It has a complicated gene activity controlling system which is related with cells and tissue differentiation in ontogenesis. The more complicated in evolutionary plan an organism is, the larger amount of DNA it contains. Eukaryotes also have excessive genes. So the human genome contains 3 billons nucleotide pairs, which is enough to make more than 2 millions structural genes. Conversely, different assessments of the human genome have from 50000 to 100000 structural genes. This is in 20-40 times less than possible. More than half of the genome consists of unique genes, which are not repeated. The bull calf has 55% of such genes, human 64%, drosophila 70%.

To discover human genome sequence an international research program was designed. The research under this program is performed in many countries such as USA, Japan, EU, Russia and other. All research programs related with human genome are coordinated by HuGO council of UNESCO. The human/genome contains 3 billions nucleotide pairs. To write it in a form of letters require 2 millions sheets of paper. It requires a long time (at least 10 years) and huge funding (3 billions dollars, 1 dollar per one “letter”). The program “Human Genome” has aim to dissolve the following problems:

1. To determine human DNA structure, that means to determine all nucleotide sequences.
2. To explain physiological value of genetic texts, that means to explain the relationships between genetic sequences and physiological and hereditary traits.

3. To study molecular basis of hereditary diseases, their prenatal diagnostics, preventive measures; to study hereditary nature of allergy, immune defects, cancer, susceptibility to cardiovascular diseases, psychiatry, endocrine and other diseases.
4. To defend human genome from mutation preventing rise of genetic load (ecology aspect of program).
5. To find the ways of bacteria, plants and animal evolution.

Completing “Human Genome” program will help science and medicine to find defect genes and to start treating of hereditary diseases controlled by those genes. It also will facilitate understanding of ovum development to mature organisms. It also will help to dissolve problem of drug intolerance. It will allow constructing drugs without side effects; creating genetic library, which will help to understand events not only in human but also in all life creatures such as bacteria, plants and animals. It will allow determining all genes structure and determining correspondence between genes and traits.

However, determining genome structure of every person may lead to discrimination. Some people may be discharged from job on a base of this analysis. So that means we need to create new justice documents to prevent it.