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There is a general belief that radiation can cause genetic mutation. I have never understood the mechanism by which such mutation could result.
An alpha particle (+helium nucleus), beta particle (-electron) or a gamma ray (high energy em radiation with a wavelength smaller than an atomic diameter) whizzing through a strand of DNA could obviously break some chemical bonds and knock out some atoms. But it is not going to substitute one nucleic acid (each with a molecular weight of about 500) for another and change the genetic code. The effect will be a random rearrangement of some of the constitutent atoms, not a change in the genetic code.
I conclude that radiation alone cannot physically cause genetic mutation. If it causes mutation it must do so by triggering some biological process that results in mutation. So what is the biological mechanism by which radiation is supposed to cause genetic mutation?
AM
An alpha particle (+helium nucleus), beta particle (-electron) or a gamma ray (high energy em radiation with a wavelength smaller than an atomic diameter) whizzing through a strand of DNA could obviously break some chemical bonds and knock out some atoms. But it is not going to substitute one nucleic acid (each with a molecular weight of about 500) for another and change the genetic code. The effect will be a random rearrangement of some of the constitutent atoms, not a change in the genetic code.
I conclude that radiation alone cannot physically cause genetic mutation. If it causes mutation it must do so by triggering some biological process that results in mutation. So what is the biological mechanism by which radiation is supposed to cause genetic mutation?
AM