The basis of this year's important revolution
by Tamara Traubman
What is DNA?
DNA is a coiled ladder, made of a sequence of chemical units. There are four types of units, and they are marked with the letters A, T, G, C. The total human DNA is called a genome, and it contains about 3 billion DNA units. The genetic information is written in the various combinations of DNA letters.
What is a garden?
A gene is a segment of DNA that contains a recipe for protein production. The proteins carry out all the functions of the body: for example, determine the color of the skin, process nutrients and transmit messages between cells. Genes do not cause diseases: defects in the DNA sequence in the gene cause the formation of a defective protein, which is the cause of the disease.
Is my genome the same as others?
Only about 0.1% of the genome differs from person to person. In this fraction of a percentage are written the genetic instructions that control, for example, the color of the hair and the tendency to get diseases.
can we live forever
No. But life expectancy is increasing, and according to the predictions, by the middle of the century, 2.2 million people will have the privilege of celebrating their 100th birthday. The human genome project will help decipher molecular mechanisms that control aging, mainly to discover how to suspend their action, and less with the aim of extending life.
Can we determine the eye color of our children?
Not in the near future. The genes responsible for eye color have no medical importance, so scientists do not bother to look for them.
Can we replace our genes?
It seems that we will be able to make repairs in them with the experimental technology of gene therapy, in which damaged genes are replaced with normal genes.
How much did it cost to decode the human genome?
So far, the American government has invested more than 2.53 billion dollars in the project (3-5% of which is dedicated to researching ethical, legal and social issues). The British Valcom Foundation - a philanthropy fund that finances most of the genome project in the UK - invested another several hundred million dollars. The Celera company, which competes in the project, has also invested several hundred million. However, the cost of the project has decreased greatly over the years: about five years ago, decoding a pair of DNA units cost about 2 dollars, today it costs 10 cents.
In any case, the cost of the project is dwarfed in comparison to the profits of the project, in the understanding of basic biological processes, in the understanding of the development of diseases and finally, perhaps, in the cure as well.
Can we duplicate ourselves?
The good news is that since Dolly the cloned sheep was born, about three years ago, scientists have made great progress in cloning research. In the list of animals that have been cloned so far, you can find mice, pigs, cows and even monkeys. However, behind every birth of a cloned animal are hundreds of unsuccessful attempts, and scientists still struggle to understand the process to its end. The real answer will become clear only when someone actually tries to clone a person.
Will we live in a world without diseases?
No. Although the World Health Organization has declared smallpox as a disease that has disappeared from the world, and within a year it intends to complete the eradication of polio, but the rapid evolution of bacteria and viruses ensures that there will always remain harmful factors that will be able to overcome the drugs. In addition, it is impossible to prevent the natural process of the formation of random mutations in the human genome - at least not in natural reproduction.
Will world hunger end?
In principle, science today has an effective tool - genetic engineering - that can solve the plight of hunger. According to the World Health Organization, almost a billion are hungry today and another 2.5 billion suffer from malnutrition. Agricultural areas are shrinking, the amount of available water is decreasing, and according to the conservative scenario, by the year 2025, food production must increase by at least 25% to provide the food needed for population growth.
However, it is not clear to what extent the genetically modified plants will be available in poor countries. Also in the West, by the way, they are opposed by many religious groups and organizations for the protection of the environment. However, demographers and scientists believe that genetic engineering is the only realistic means that can meet the necessary increase in food production, by creating nutritious crops that have genes that make them resistant to pests and harsh climatic conditions.
Are Jews more exposed to genetic diseases?
Since the Jews have always lived in closed communities, there are genetic mutations that are characteristic of them. In addition, there seem to be certain mutations that are more common among Ashkenazim. The reason may be that they come from a small founding community. Thus, for example, one out of 40 Jews has a mutation in the BRCA1 or BRCA2 genes (which increases the risk of getting breast or ovarian cancer). In the non-Jewish population, the frequency of mutation in these genes is one in 300
Dr. Yoel Zalotogura, director of the Department of Community Genetics at the Ministry of Health, says that every year in Israel about 25 carrier tests are done for Tay-Sachs, a disease that affects almost only Ashkenazim, and in recent years the disease has almost disappeared. The incidence of thalassemia, which mainly affects Arabs and Jews of Mediterranean origin, has also decreased considerably.
* The knowledge site was until the end of 2002 part of the IOL portal of the Haaretz group
