Daily Archives: October 30, 2017

Russian roulette…

Just a quickie this week….

It’s Year 10 and the grim effects of smoking. The biology is interesting, though I must admit I prefer to celebrate the power of data to do good things (Richard Doll) and get them thinking about experimental design (how to show a causal link between smoking and cancer?). The following exercise is designed to cover these learning outcomes and doesn’t need much comment from me (though do look at the wonderful quote from James 1st/6th!).

Smoking and Epidemiology and Richard Doll November 2017

But how to convey the sense of genetic Russian roulette that is random mutation?

For this, I came up with the following interactive Powerpoint…

Random mutations in DNA interactive

The first slide just introduces chromosomes and we have a very basic chat about genetics and the idea of coded information.


A mutation, I explain, is just a random change to that information – the key point is, it could occur anywhere….

The second slide indicates 22 loci (the blue circles).

chromosomes 2

I ask a student to pick a blue circle, a locus. Any one they like. Clicking on the blue circle will, 21 times out of 23, take them to a slide saying:

Silent mutation

No effect no person

Clicking on the smiley face takes them back to the second slide, and the locus they selected magically disappears. We talk about the idea of silent mutations. Another student picks another circle, with, one hopes, the same effect.

But at some point, somebody will choose the bottom circle of the two on chromosome 7. Clicking on this circle takes them to this message:

Mutation to onco-gene

Uncontrolled cell division


So I hope they take home the idea of random mutations and that smoking is like playing Russian roulette with your genes, but also the idea that the more you smoke, the more you increase that risk.

Short and sweet – let me know what you think!