The mutation is found principally in Europe and western Asia, with higher frequencies generally in the north. Homozygous carriers of the Delta32 mutation are resistant to HIV-1 infection because the mutation prevents functional expression of the CCR5 chemokine receptor normally used by HIV-1 to enter CD4+ T cells.
Q. What is the Delta 32 mutation?
A genetic mutation known as CCR5-delta 32 is responsible for the two types of HIV resistance that exist. The mutation causes the CCR5 co-receptor on the outside of cells to develop smaller than usual and no longer sit outside of the cell. CCR5 co-receptor is like door that allows HIV entrance into the cell.
Table of Contents
- Q. What is the Delta 32 mutation?
- Q. Is CCR5 Delta 32 common?
- Q. Can you be tested for CCR5 Delta 32?
- Q. Does everyone have the CCR5 gene?
- Q. What was O Brien’s hypothesis about the mutated CCR5 d32 gene?
- Q. What disease was suspected of causing the outbreak in Eyam?
- Q. How does mutation contribute to evolution?
- Q. What is the scientific explanation for those who survived the plague?
Q. Is CCR5 Delta 32 common?
Geneticists say that the CCR5 delta 32 mutation existed as many as 2,500 years ago, but back then it likely occurred in only 1 in 20,000 Europeans, as compared to 1 in 10 today.
Q. Can you be tested for CCR5 Delta 32?
Genetic testing can be done on several genes that affect HIV and the course of the infection. For example, a genetic mutation causing a protein defect called CCR5 delta 32 has been shown to be resistant to the HIV virus.
Q. Does everyone have the CCR5 gene?
He turned out to be missing just 32 letters in a gene called CCR5, and remarkably, it was enough to make him resistant to the virus killing so many others. About 1 percent of people of European descent carry two copies of this mutation, now known as CCR5-Δ32.
Q. What was O Brien’s hypothesis about the mutated CCR5 d32 gene?
Stephen O’Brien felt that the mutated CCR5 gene, delta 32, may have prevented the plague from being able to enter its host’s white blood cells. Specifically, Eyam was an isolated population known to have survived a plague epidemic.
Q. What disease was suspected of causing the outbreak in Eyam?
On 1 November 1666 farm worker Abraham Morten gasped his final breath – the last of 260 people to die from bubonic plague in the remote Derbyshire village of Eyam.
Q. How does mutation contribute to evolution?
Mutation plays an important role in evolution. Mutation is important as the first step of evolution because it creates a new DNA sequence for a particular gene, creating a new allele. Recombination also can create a new DNA sequence (a new allele) for a specific gene through intragenic recombination.
Q. What is the scientific explanation for those who survived the plague?
If people’s susceptibility to the plague was somehow genetic — perhaps they had weaker immune systems, or other health problems with a genetic basis — then those who survived might pass along stronger genes to their children, resulting in a hardier post-plague population.
