Have you ever wondered what is inside your dental plaque? Probably not, but people like me do. I'm an archeological geneticist at the Center for Evolutionary Medicine at the University of Zurich, and I study the origins and evolution of human health and disease by conducting genetic research on the skeletal and mummified remains of ancient humans. And through this work, I hope to better understand the evolutionary vulnerabilities of our bodies, so that we can improve and better manage our health in the future.
Jeste li se ikad zapitali što se nalazi unutar vašeg zubnog plaka? Vjerojatno niste, no ljudi poput mene jesu. Ja sam arheološka genetičarka u Centru za evolucijsku medicinu Sveučilišta u Zurichu i proučavam porijeklo i evoluciju ljudskog zdravlja i bolesti provođenjem genetskih istraživanja na koštanim i mumificiranim ostacima drevnih ljudi. Kroz taj rad nadam se da ću bolje razumjeti evolucijsku ranjivost naših tijela, kako bismo mogli poboljšati i bolje upravljati našim zdravljem u budućnosti.
There are different ways to approach evolutionary medicine, and one way is to extract human DNA from ancient bones. And from these extracts, we can reconstruct the human genome at different points in time and look for changes that might be related to adaptations, risk factors and inherited diseases. But this is only one half of the story.
Postoje različiti pristupi evolucijskoj medicini, a jedan je od njih izvlačenje ljudske DNK iz drevnih kostiju. Iz tih uzoraka možemo rekonstruirati ljudski genom u različitim vremenskim točkama i tražiti promjene koje bi mogle biti povezane s prilagodbama, rizične čimbenike i nasljedne bolesti. No to je samo polovica priče.
The most important health challenges today are not caused by simple mutations in our genome, but rather result from a complex and dynamic interplay between genetic variation, diet, microbes and parasites and our immune response. All of these diseases have a strong evolutionary component that directly relates to the fact that we live today in a very different environment than the ones in which our bodies evolved. And in order to understand these diseases, we need to move past studies of the human genome alone and towards a more holistic approach to human health in the past.
Najvažnije današnje zdravstvene izazove ne uzrokuju jednostavne mutacije našeg genoma, nego su posljedica složene i dinamične međuigre između genskih varijacija, prehrane, bakterija i parazita te naše imunološke reakcije. Sve te bolesti posjeduju snažnu evolucijsku komponentu izravno povezanu s činjenicom da danas živimo u mnogo različitijoj okolini od one u kojoj su naša tijela evoluirala. Kako bismo razumjeli te bolesti moramo se odmaknuti od samog proučavanja ljudskog genoma prema holističkom pristupu ljudskom zdravlju u prošlosti.
But there are a lot of challenges for this. And first of all, what do we even study? Skeletons are ubiquitous; they're found all over the place. But of course, all of the soft tissue has decomposed, and the skeleton itself has limited health information. Mummies are a great source of information, except that they're really geographically limited and limited in time as well. Coprolites are fossilized human feces, and they're actually extremely interesting. You can learn a lot about ancient diet and intestinal disease, but they are very rare.
No za to se moramo suočiti s mnogim izazovima. Kao prvo, što zapravo proučavamo? Kosturi su sveprisutni, ima ih posvuda. No, naravno da se svo meko tkivo razgradilo, a sam kostur nudi ograničene informacije o zdravlju. Mumije su odličan izvor podataka, samo što su ograničene geografski i vremenski. Koproliti su fosilizirani ljudski izmet i zapravo su vrlo zanimljivi. Možete saznati mnogo o drevnoj prehrani i bolestima probavnog sustava, no vrlo su rijetki.
(Laughter)
(Smijeh)
So to address this problem, I put together a team of international researchers in Switzerland, Denmark and the U.K. to study a very poorly studied, little known material that's found on people everywhere. It's a type of fossilized dental plaque that is called officially dental calculus. Many of you may know it by the term tartar. It's what the dentist cleans off your teeth every time that you go in for a visit. And in a typical dentistry visit, you may have about 15 to 30 milligrams removed. But in ancient times before tooth brushing, up to 600 milligrams might have built up on the teeth over a lifetime.
Kako bismo se pozabavili tim problemom, okupila sam međunarodni istraživački tim u Švicarskoj, Danskoj i Ujedinjenom Kraljevstvu da bi proučavao slabo istražen i malo poznat materijal koji pronalazimo na ljudima svugdje. To je vrsta fosiliziranog zubnog plaka koja se službeno naziva zubni kalkulus. Mnogi od vas ga znaju pod nazivom kamenac. To je ono što zubar čisti s vaših zuba svaki put kad ga posjetite. Kod tipičnog posjeta zubaru mogli bi vam ukloniti 15 do 30 miligrama. No u drevno doba, prije pranja zuba četkicom, na zubima se moglo nakupiti do 600 miligrama tijekom životnog vijeka.
And what's really important about dental calculus is that it fossilizes just like the rest of the skeleton, it's abundant in quantity before the present day and it's ubiquitous worldwide. We find it in every population around the world at all time periods going back tens of thousands of years. And we even find it in neanderthals and animals.
Kod zubnog je kamenca doista važno to što se on fosilizira poput ostatka kostura, količinski ga ima mnogo prije suvremenog doba i sveprisutan je diljem svijeta. Pronalazimo ga u svakoj populaciji diljem svijeta u svim vremenskim razdobljima desecima tisuća godina unazad. Pronalazimo ga čak i kod neandertalaca i životinja.
And so previous studies had only focused on microscopy. They'd looked at dental calculus under a microscope, and what they had found was things like pollen and plant starches, and they'd found muscle cells from animal meats and bacteria. And so what my team of researchers, what we wanted to do, is say, can we apply genetic and proteomic technology to go after DNA and proteins, and from this can we get better taxonomic resolution to really understand what's going on?
Prethodne su se studije usredotočavale samo na mikroskopiju. Pregledali bi zubni kamenac pod mikroskopom i pronalazili stvari poput peludi, biljnog škroba, mišićnih stanica iz životinjskog mesa i bakterije. Moj je istraživački tim želio primijeniti, recimo, genetsku i proteomsku tehnologiju da bismo krenuli u potragu za DNK i bjelančevinama iz kojih bismo mogli dobiti bolju taksonomsku razlučivost da bismo doista razumjeli što se događa.
And what we found is that we can find many commensal and pathogenic bacteria that inhabited the nasal passages and mouth. We also have found immune proteins related to infection and inflammation and proteins and DNA related to diet. But what was surprising to us, and also quite exciting, is we also found bacteria that normally inhabit upper respiratory systems. So it gives us virtual access to the lungs, which is where many important diseases reside.
Otkrili smo da možemo naći mnoge komenzalne i patogene bakterije koje su živjele u nosnim prolazima i ustima. Također smo pronašli imunološke proteine povezane s infekcijama i upalama i proteine i DNK povezane s prehranom. No iznenadilo nas je, i poprilično uzbudilo, to što smo također pronašli bakterije koje inače žive u gornjem dišnom sustavu. To nam praktički daje pristup plućima gdje se nalaze mnoge važne bolesti.
And we also found bacteria that normally inhabit the gut. And so we can also now virtually gain access to this even more distant organ system that, from the skeleton alone, has long decomposed. And so by applying ancient DNA sequencing and protein mass spectrometry technologies to ancient dental calculus, we can generate immense quantities of data that then we can use to begin to reconstruct a detailed picture of the dynamic interplay between diet, infection and immunity thousands of years ago.
Također smo pronašli i bakterije koje inače žive u crijevima. Tako sad možemo praktički pristupiti tom još udaljenijem organskom sustavu koji se, izuzev samog kostura, davno razgradio. Tako primjenom sekvenciranja drevne DNK i tehnologija masene spektrometrije proteina na drevni zubni kamenac, možemo dobiti ogromne količine podataka koje možemo upotrijebiti za rekonstrukciju detaljne slike dinamičkog uzajamnog djelovanja između prehrane, infekcija i imuniteta prije više tisuća godina.
So what started out as an idea, is now being implemented to churn out millions of sequences that we can use to investigate the long-term evolutionary history of human health and disease, right down to the genetic code of individual pathogens. And from this information we can learn about how pathogens evolve and also why they continue to make us sick. And I hope I have convinced you of the value of dental calculus.
Što je započelo kao ideja, sad se primjenjuje da bi izbacilo milijune sekvenci koje možemo upotrijebiti da bismo istražili dugotrajnu evolucijsku povijest ljudskog zdravlja i bolesti, sve do genetskog koda pojedinih patogena. Iz tih podataka možemo saznati kako patogeni evoluiraju i zašto se od njih i dalje razbolijevamo. Nadam se da sam vas uvjerila u vrijednost zubnog kamenca.
And as a final parting thought, on behalf of future archeologists, I would like to ask you to please think twice before you go home and brush your teeth.
Kao konačna misao na rastanku u ime budućih arheologa željela bih vas zamoliti da dvaput razmislite prije no što odete kući i operete zube.
(Applause)
(Pljesak)
Thank you.
Hvala vam.
(Applause)
(Pljesak)