The offices and laboratories may be shiny and modern, but CSI Miami it ain’t. On a damp, grey Scottish morning, the SASA complex on the western fringes of Edinburgh feels a million miles away from Florida’s steamy tropical surroundings. A million miles away from the heat and dust of the African savannah too, come to that. Passing through security we spot a poster about potatoes. SASA, aka Science and Advice for Scottish Agriculture, is, among other things, home to the British Potato Variety Database.
This is not the place you’d expect to find scientists applying cutting edge technology to help fight the illegal trade in rhino horn.
We’re greeted by Dr Lucy Webster, and her colleague, Kara Dicks. Lucy is senior molecular biologist at SASA’s wildlife DNA forensics unit, charged with providing analytical and forensic support for the investigation of wildlife crimes to the Scottish Government. Kara is working on her University of Chester PhD, on the conservation genetics of black rhino. Together they are applying the latest DNA profiling techniques to rhino horn, in an initiative which could eventually lead to a DNA database of horns from museums and collections around the UK, and possibly further afield.
The soaring price of black market rhino horn in the Far East has led to a spate of thefts of horn from museums across Europe. With horn now worth more than gold or cocaine, it’s a commodity that’s attracted the attention of organised criminal gangs. Many museums have been forced to take genuine horns off display and replace them with plastic or glass fibre replicas.
Showing us round the forensic laboratories, Lucy explains how DNA profiling tests could be used to track back confiscated horns, even those that have been ground down into powder, to identify where they were stolen from and help bring about successful prosecutions.
DNA profiling is already being used in South Africa to identify horns from wild rhinos killed by poachers in game reserves and to help trace smuggling routes. Lucy and Kara now want to find out whether DNA profiling can also work with older horns.
‘Working with Dr Ross McEwing of the Royal Zoological Society of Scotland, we’ve sampled all the rhino horn at the Museum of Scotland (where none is now on display). Some of these are more than 100 years old. We don’t know at this stage if DNA from a 100 year old rhino horn is going to give us a good enough sample. Older samples have less DNA and the DNA that there is may be degraded,’ explains Lucy. ‘We suspect older samples may be harder to work with. But we’re keen to give it a shot. From a population genetics perspective the older samples could be really interesting.’
Lucy explains the DNA profiling methodology is essentially similar to profiling human DNA. It involves amplifying 16 different parts of the rhino genome:
‘We start by drilling shavings from the inside of the horn. We’ll then take a sub-sample of that and extract the DNA using various enzymes and buffers, usually at about 60oC over two nights. This incubation step extracts the DNA from the keratin matrix. Once we have the DNA we can then run the profiling tests, to identify the 16 different parts of the rhino genome.’
‘For each part each animal will have two copies, one inherited from their mother, one from their father. These copies may differ in length. They’re not genes, they’re part of non-coding DNA. These different length variants, all of the different 16 markers, produce your DNA profile. Based on the frequency of the different variants, you can work out the probability of identifying the individual from members of the population.
Lucy and Kara are keen to emphasise the project is very much in its pilot stage, with Kara currently working to validate the markers. Once it’s been shown the technique works it could then be applied to further samples from around the country.