Two years ago, Dr. Kathryn Robson, a senior scientist at the WIMM, ran a five-week course on Life Sciences for 10-11 year olds at a primary school in Abingdon. Using the pedigree cats that she breeds, Dr. Robson introduced the concept of genetic inheritance and a complex biological phenomenon known as X-inactivation to a very young audience. This month, one of the famous felines (then merely a kitten) gave birth to her own litter of kittens. To mark the anniversary, here Dr Robson explains how (sometimes!) working with children and animals can actually do the trick…
The Launchpad programme, run by Dunmore Primary School in Abingdon, allows children to choose any course ranging from recreational interests to cycling proficiency and more academic topics, offering a taster of what is to come at secondary school.
One of the sessions on offer focused on genetics, explaining how and why parents’ characteristics are passed onto their children. As I breed and show Birman cats as a hobby, I used a litter of kittens to introduce this concept, scientifically termed genetic inheritance. Unsurprisingly, the children were hugely excited when they saw the kittens (thankfully, none of them had allergies!)
To explain the science behind genetic inheritance, pairs of children were given a bag containing two colours of Lego bricks. The different colours represented the information passed on from each parent. I explained that this information is found in a long string of letters known as DNA. Rope was used to represent DNA, and the children were asked to twist it back on itself to show how such a huge structure containing so much information can be packaged into a very small space. Then each child added some alcohol to a tube containing a solution of DNA and watched the DNA appear, as if by magic.
Thinking that this was more than enough information for one day, what I had not bargained for was a little voice at the back of the room then asking how some of the kittens had got a tortoiseshell coat (basically a mixture of three different coat colours). Whilst the male kitten was ginger, all three of the female kittens were tortoiseshell – why was the male kitten not patchy like his sisters? And why did none of the female kittens look like their mother?
The answer lies in a complicated biological phenomenon, unique to all female mammals resulting in pieces of DNA becoming inactivated; a process known as X-inactivation. This means that the information in the inactivated piece of DNA cannot be accessed – and it just so happens that in cats, this portion of DNA contains the information that controls coat colour.
However – if that wasn’t complicated enough, there is another twist to the tail (!) This process of X-inactivation in females doesn’t occur in the same way all the time, which is why, in female kittens, some patches of fur are different colours to others.
I didn’t ever intend to go into this much detail on a topic that is almost degree-level biology – but the appeal of the kittens inspired the childrens’ curiosity and to my surprise they grasped the concept quickly. Coincidentally, the process of DNA inactivation in females was discovered at the neighbouring MRC unit by Mary Lyon, which now bears her name. We still do not fully understand how X- inactivation works but we do know that it is important in a range of human disorders, including muscular dystrophy and colour blindness , and remains a hot topic in current biological research.
The lesson they learnt: how genetic information is passed on from parents to their offspring. The lesson I learnt: never underestimate a 10-year old.
Post edited by Bryony Graham, Gemma Swiers and Raffaella Facchini.