Doctoral (PhD) student position in Early-life Microbial Exposures and Type 1 Diabetes

Stockholm, Sweden

2026-04-03 (Europe/Stockholm)

Do you want to contribute to top quality medical research?

To be a doctoral student means to devote oneself to a research project under supervision of experienced researchers and following an individual study plan. For a doctoral degree, the equivalent of four years of full-time doctoral education is required.

The research group

The Flodström Tullberg group is studying the natural history of type 1 diabetes and dedicated to advancing the development of preventative treatments. The research conducted by the group primarily explores environmental triggers, such as common viral infections and microbial exposures. With a strong translational focus, the group integrates cutting-edge molecular, cellular, and model systems to bridge fundamental research with clinical applications. Internationally recognized as a leader in the study of environmental factors linked to type 1 diabetes, the group has contributed several high-impact publications in recent years (Science Advances 2020, 2024; Diabetes, 2021, Diabetologia 2025).

The doctoral student project and the duties of the doctoral student

Early exposure to a diverse range of environmental microbes is thought to play a crucial role in shaping the developing immune system and supporting its health‑promoting functions. Growing evidence suggests that microbial diversity in early life may influence the risk of developing type 1 diabetes. Because children spend substantial time in daycare settings, the main aim of this doctoral project is to examine microbial richness and diversity in outdoor daycare environments across rural and urban areas of Sweden. Together with work in an experimental model, the project will assess whether environmental microbiota are linked to type 1 diabetes risk.

The project builds on an extensive collection of environmental samples gathered from sandpits and other outdoor areas at more than 180 daycares nationwide. The work involves DNA extraction and characterization of microbial communities using 16S rRNA gene sequencing, followed by bioinformatic analysis. It further includes applying hierarchical and mixed‑effects models and integrating microbiome data with environmental variables derived from high‑resolution aerial imagery, geospatial datasets, and AI‑assisted land‑cover classification Additionally, national diabetes registries will be used to map local type 1 diabetes incidence across Sweden.. Over the first three years, the doctoral student will also conduct fieldwork by carrying out three rounds of sampling at selected daycares during winter, spring, and fall.

The candidate is expected to contribute to experimental design, experimentation, data analyses and publication of results. Furthermore, the candidate will participate in various research-related activities including group meetings, departmental seminars, national/international scientific meetings, as well as contribute to routine work within the research group and help supervise master’s students.

The successful candidate will become part of a dynamic research environment at the Department of Medicine, Huddinge, Karolinska Institutet.

What do we offer?

A creative and inspiring environment full of expertise and curiosity. Karolinska Institutet is one of the world's leading medical universities. Our vision is to pursue the development of knowledge about life and to promote a better health for all. At Karolinska Institutet, we conduct successful medical research and hold the largest range of medical education in Sweden. As a doctoral student you are offered an individual research project, a well-educated supervisor, a vast range of elective courses and the opportunity to work in a leading research group. Karolinska Institutet collaborates with prominent universities from all around the world, which ensures opportunities for international exchanges. You will be employed on a doctoral studentship which means that you receive a contractual salary. Employees also have access to our modern gym for free and receive reimbursements for medical care.

Eligibility requirements for doctoral education

In order to participate in the selection for a doctoral position, you must meet the following general (A) and specific (B) eligibility requirements at latest by the application deadline.

It is your responsibility to certify eligibility by following the instructions on the web page Entry requirements (eligibility) for doctoral education.

A) General eligibility requirement You meet the general eligibility requirement for doctoral/third-cycle/PhD education if you:

1. have been awarded a second-cycle/advanced/master qualification (i.e. master degree), or
2. have satisfied the requirements for courses comprising at least 240 credits of which at least 60 credits were awarded in the advanced/second-cycle/master level, or
3. have acquired substantially equivalent knowledge in some other way in Sweden or abroad.^*

Follow the instructions on the web page Entry requirements (eligibility) for doctoral education.

^*If you claim equivalent knowledge, follow the instructions on the web page Assessing equivalent knowledge for general eligibility for doctoral education.

B) Specific eligibility requirement

You meet the specific eligibility requirement for doctoral/third-cycle/PhD education if you:

• Show proficiency in English equivalent to the course English B/English 6 at Swedish upper secondary school.

Follow the instructions on the web page English language requirements for doctoral education.

Verification of your documents Karolinska Institutet checks the authenticity of your documents. Karolinska Institutet reserves the right to revoke admission if supporting documents are discovered to be fraudulent. Submission of false documents is a violation of Swedish law and is considered grounds for legal action.

(A) and (B) can only be certified by the documentation requirement for doctoral education.

Skills and personal qualities

For this PhD project, we are seeking a highly motivated and enthusiastic individual with a strong interest in understanding how environmental microbiomes influence the risk of developing type 1 diabetes. The ideal candidate holds a degree in molecular biology, biomedicine, cell biology, or a closely related discipline. We are looking for someone who is self‑driven, fluent in English, and possesses strong communication skills, together with the ability to collaborate effectively and contribute positively within a team environment.

Previous laboratory experience in DNA extraction and 16S rRNA sequencing is considered a strong merit, as is familiarity with programming for data analysis and bioinformatics. Prior experience in field studies—such as environmental sampling or field‑based data collection—is also regarded as a strong asset, given the hands‑on components of this project.

We place significant emphasis on personal suitability, including curiosity and enthusiasm for scientific research, strong problem‑solving skills, attention to detail, and a collaborative mindset.

Terms and conditions

The doctoral student will be employed on a doctoral studentship maximum 4 years full-time.

Application process

Submit your application and supporting documents through the Varbi recruitment system. Use the button in the top right corner and follow the instructions. We prefer that your application is written in English, but you can also apply in Swedish.

Your application must contain the following documents:

• A personal letter and a curriculum vitae
• Degree projects and previous publications, if any
• Any other documentation showing the desirable skills and personal qualities described above
• Documents certifying your general eligibility (see A above)
• Documents certifying your specific eligibility (see B above)

Selection

A selection will be made among eligible applicants on the basis of the ability to benefit from doctoral education. The qualifications of the applicants will be evaluated on an overall basis.

Karolinska Institutet uses the following bases of assessment:

• Documented subject knowledge of relevance to the area of research
• Analytical skill
• Other documented knowledge or experience that may be relevant to doctoral studies in the subject.

All applicants will be informed when the recruitment is completed.

Read more about the Malin Flodström-Tullberg group here

Want to make a difference? Join us and contribute to better health for all

Type of employment: PhD placement
Contract type: Full time
First day of employment: Omgående, enligt överenskommelse
Salary: Monthly salary
Number of positions: 1
Full-time equivalent: 100
City: Flemingsberg
County: Stockholms län
Country: Sweden
Reference number: STÖD 2-1113/2026

Contact:
1. Malin Flodström Tullberg, Manager, malin.flodstrom-tullberg@ki.se
2. Fredrika Aronsson, HR Partner, fredrika.aronsson@ki.se

Union representative:
1. Peter Svensson, SACO, peter.svensson@ki.se
2. Mari Gilljam, OFR, mari.gilljam@ki.se
3. Elizabeth Valenzuela, SEKO, elizabeth.valenzuela@ki.se

Published: 2026-03-13
Last application date: 2026-04-03