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From the lab to the field

An encounter with a community in rural Goiás transformed biologist Carlos Menck’s perspective on genetics

Menck, whose research career has been driven by a passion for genetics and evolution since he began studying a degree in biology at 17

Léo Ramos Chaves / Pesquisa FAPESP Magazine

Ever since I started my biology degree at the University of São Paulo [USP] in 1974, I have spent most of my time in the lab. I started investigating xeroderma pigmentosum (XP) for my first university research project in 1977. It is a noncontagious genetic disease characterized by extreme sensitivity to ultraviolet radiation. Affected individuals are highly susceptible to skin cancer. But I only actually met anybody with the disease 30 years later. Until 2004, I studied cells solely in the lab, but interacting with real patients changed my path.

In 2010, we were made aware of a community in Faina, in the interior of Goiás, where the disease is much more common than elsewhere. We did some calculations and found that one in every 400 people there are diagnosed with the disease, while average rates around the world range from one in every 200,000 to one in a million. Marriage between close relatives is common in Faina, which explains the high frequency of the disease. At the time, we identified 20 XP patients from a population of approximately 7,000 people. The diagnosis is no longer an isolated issue in the community as we are used to seeing elsewhere. It is a common occurrence. Faina is what we call a cluster community—a location where there are many people with a usually rare genetic disorder.

After we found out about the community, our team of biologists developed a strong relationship with the local population, with far-reaching consequences. We discovered, for example, that the mutation occurred in a gene responsible for DNA replication. We thus started investigating DNA replication more than we had been doing beforehand. One of the most positive outcomes of this fieldwork is that it has given us the opportunity to build human relationships. I had never before had such close human contact with a “research subject,” for want of a better term.

The exchanges of our scientific research proved to be very fruitful. We now do DNA sequencing to check for genetic mutations. If a mutation is confirmed, we have a molecular diagnosis of the disease. The patients, meanwhile, help us expand our knowledge of the disease and the predisposition to and occurrence of certain types of cancer. They give us a better understanding of how the human body functions and the aging process. These are just some of the questions we are answering with the help of these patients—some of which I have been seeking answers for since high school. I remember a biology class about DNA and genetic inheritance that left a deep impression on me, I think I must have been about 15 years old at the time. I was fascinated by the subject and started reading everything I could about it. My father was a salesman and my mother a housewife. They had little formal education, but they always encouraged their children to read and study, so much so that my three siblings and I all went to university.

I started my biology degree when I was 17 and developed a passion for genetics and evolution until I discovered molecular biology, which involves studying the interactions between DNA, RNA, and proteins, as well as how these interactions are regulated. I always wanted to do scientific research. My parents and siblings thought it would be impossible in Brazil, that I would have to move abroad because the conditions here were so difficult. I decided to give it a try in Brazil and leave if it did not work out. In the third year of my degree, when I started working with Professor Rogério Meneghini, I saw that it was indeed possible. He challenged his students with scientific approaches and methodologies that proved extremely useful to answering the questions we asked through our undergraduate research.

Personal ArchiveIn Faina, in rural Goiás, xeroderma pigmentosum is far more common than elsewhere. To prevent skin cancer, those diagnosed with the disease try to avoid exposure to ultraviolet radiationPersonal Archive

Meneghini played a crucial role in my career, providing many benchmarks in research quality and at the same time encouraging important reflections on scientific work. It was him who encouraged me to go straight into studying my PhD in 1978. I was armed with the results of my undergraduate research project, in which I identified how lesions caused by ultraviolet light are repaired and replicated in mammalian cells. My biochemistry doctoral thesis, supervised by Meneghini, was an offshoot of this project. I identified how DNA lesions are replicated in mammalian cells. I defended the thesis at USP in 1982.

When I was around 26, having completed my PhD, Roberto Alcântara-Gomes invited me to join the biophysics department of the Institute of Biology at the State University of Rio de Janeiro [UERJ]. I stayed there for three years. It was a wonderful experience because it gave me financial peace of mind and I was able to work on another great passion of mine: teaching. To this day I am still friends with some of my undergraduate students from back then. I saw what it was like to carry out research outside USP, which was an extremely positive experience, and my eyes were opened to some of the challenges that we did not face there, mainly relating to funding. At UERJ, the laboratory did not yet have the equipment needed to study mammalian cells and the Rio de Janeiro State Research Foundation [FAPERJ] did not fund the research. We relied on support from the federal government via the Brazilian National Council for Scientific and Technological Development (CNPq).

In 1985, I had the opportunity to do a postdoctoral fellowship in France, in Alain Sarasin’s lab at the Atlantic Cancer Research Institute in Villejuif, near Paris. It was another incredible experience. For us Brazilians, working with such impressive facilities was unimaginable. In addition to the material resources, they were able to quickly obtain inputs and support of technicians who assisted in the research, as well as the potential for dialogue with other scientists studying the same topic. My time abroad also helped me realize for certain that I wanted to develop my scientific career in Brazil, to do my research here, and above all, to teach. After three years in Paris, two with a grant from CNPq and one with a grant from France, I decided to return to USP. Not just because it was at USP that everything started for me, but primarily because of what FAPESP represented—and still represents—in fostering research. There was also the issue of autonomy. I did not need to target my research to a particular area of interest based on the funding source.

Since then, I have continued investigating genetics and DNA repair systems, studying the genome’s protection mechanisms against physical and chemical aggression from the cellular environment. These DNA repair systems are related to the genesis of tumors and aging, for example. To understand how things work, you have to dive into your research and become fully involved. It is not something you can do half-heartedly.

I always say that I lack creativity, because I am still working with the same cells that I studied during my degree. It is just a joke, because I am always surprised by molecular discoveries. One cell is never the same as another. The DNA molecule remains one of my greatest passions, but today I am also very interested in RNA. While DNA holds genetic information, RNA is responsible for synthesizing proteins in the cells. I have been a researcher for more than 40 years and I never cease to be amazed by the mysteries of life. Who can say where the research will take us?