A single nucleotide polymorphism is a variation in the sequence of molecules that make up DNA. “Polymorphism” refers to the possibility that different molecules can take a specific position in a larger molecule such as a strand of DNA. “Nucleotide” refers to the four molecules that make up DNA strands. And “single” refers to a difference in just one place on the DNA strand that can have significant biological and health effects.
As you know, the sequence of nucleotides in a strand of DNA is what holds the information from which biologically active molecules such as enzymes and proteins are made. Polymorphism in the DNA leads to polymorphisms in the one or more enzymes or proteins produced from the DNA sequence—the enzyme or protein polymorphism coming from different sequences of amino acids, the molecules that make up enzymes and proteins. A change in one amino acid can lead to a change in how well an enzyme or protein works.
In the most recent issue of the journal Leukemia and Lymphoma, Chinese researchers examined one such single nucleotide polymorphism and its effect on the risk of leukemia in children exposed to weak electromagnetic fields from electric power lines and transformers. Children who had a specific variation of this polymorphism (a SNP for short) were almost four times as likely as children with the more common SNP to suffer from acute leukemia.
Critics of the extensive research showing a relationship between childhood leukemia and power lines and other sources of weak EMF exposures claim that the energy is too weak to cause the DNA damage that results in cancer. What this latest research suggests is that EMF exposure doesn’t break DNA directly. Instead, it disrupts the enzymes responsible for repairing DNA breaks caused by other exposures.
What I just said has two parts.
All manner of things happen to us all the time that cause breaks in the necklace of nucleotides that make up our DNA. These can be ionizing radiation from ultraviolet light, CT scans, dental X-rays, and, of course, atomic bombs. Breaks can also happen as a result of toxic exposures, for example from the chemicals in tobacco smoke. But we have genes that produce enzymes that patch up these breaks. The Chinese researchers were looking at one of the SNPs in one of the genes responsible for DNA repair enzymes. They looked at that SNP because previous research found it associated with both breast and prostate cancer.
So that’s part one. Part two is that what put children at risk wasn’t a variation in a nucleotide sequence. What put them at risk were exposures that broke their DNA and thwarted their little body’s natural capacity to protect itself.
The point of this research is not that you need to have your children tested for this particular SNP. The point is to minimize their exposure in the first place: less radiation, both ionizing and EMF (which includes both firsthand and secondhand exposures from cell phones, wireless routers, Blackberry’s, and all the other marvels of the digital age); and less chemical exposure, such as tobacco smoke, volatile organic chemicals, and pesticides.
DNA has the capacity to repair itself. It’s part of our body’s capacity to heal. It’s part of our children’s body’s capacity to heal. It’s quiet amazing. We should honor our biology and stop creating burdens that an increasing number children cannot bare.
