Researchers have discovered that a rare protein in the human body protects against the infectious disease that still kills thousands
by Tamara Traubman
Researchers have identified a genetic mutation that provides almost complete protection against malaria. A slight change in the sequence of the DNA units was found in the genetic load of the mutation carriers; And this change causes their bodies to produce a protein of the hemoglobin type, which is slightly different from that of other people. This protein is called "hemoglobin C." According to Dr. Mario Coluzzi from the University of Rome, who headed the study, the discovery may allow the development of new drugs or vaccines that mimic the way hemoglobin C works.
Malaria is an infectious disease that causes fever and chills, anemia and other complications that can cause death if they are not treated. According to the World Health Organization, every day in Africa about 3,000 children die from the disease.
The researchers prefer to call the discovered mutation "genetic variation", because the concept of mutation is associated in the public mind with negative genetic changes that cause diseases. In the past, a genetic variation that protects against malaria has already been discovered, and this variation also caused a change in hemoglobin - called "hemoglobin S".
However, it turned out that this protection has a heavy price: people who inherit two copies of the hemoglobin S gene from their parents develop severe sickle cell anemia.
"The hemoglobin variation," says Dr. Colozzi, "is the first that does not 'charge' for the immune protection it provides." In other words, Coluzzi and his research partners did not find any negative effects of the newly discovered variation.
The beginning of the discovery is the hypothesis of Coluzzi and his colleagues, that hemoglobin C may provide some protection against malaria. This, following previous studies that hinted at a link between the genetic variation and the disease.
In order to test the relationship between hemoglobin C and malaria, the blood of 4,335 children from the West African country of Burkina Faso was tested. The children belonged to three groups: healthy children (3500); Children sick with severe malaria (359); and children who had less severe symptoms of the disease (476). From the blood samples, the researchers isolated the DNA, and checked which variation of hemoglobin was found in each of the groups.
The differences found between the groups were amazing: almost all the sick children had the normal version of the gene, and almost all the healthy children had the protective C version. According to the calculations made by Dr. Colozzi, the chance of subjects who inherited two copies of the protective gene from their parents - one from the mother and one from the father - of contracting malaria is 93% less than the risk of subjects without the genetic variation. Even those who inherited only one copy of the gene - from one of the parents - enjoy some protection, and their chance of contracting malaria is 26% lower than a person with a normal genetic load.
"If we find a way to provide this protein to people who live in areas infected with malaria, and who do not carry the gene, or to increase the protein levels in people who carry only one copy of it, we may have a more effective treatment against malaria," said Dr. Colozzi. However, he added that "it is unlikely that the new information will be translated into a drug in the near future."
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