Åsa Johansson – The role of genetics and epigenetics on human health

Pipette and test tube rackThe aim of my research is to determine how genetic and epigenetic factors influence human phenotypes, clinical variables and risk of disease. I also study how environmental factors introduce epigenetic alterations, with subsequent long-term health related effects.

I have three main research interests: 

The role of epigenetic changes in the etiology of human disease

Diet and lifestyle affect our health and risk for diseases. We also know that factors such as smoking, hunger and lack of sleep affects our genes through alterations in the DNA methylation. The goal of my research is to further explore the effect of diet and lifestyle on DNA methylation, and subsequent medical conditions.

I also investigate the role of DNA methylation in regulating the activity of our genes. DNA methylation modifications are reversible, and knowledge can in the future lead to development of new drugs and methods for treating various diseases.

The results from this project will lead to better understanding off how diet and lifestyle can affect the health of a population over time and also the health of the next generation through transmission of DNA methylation alterations to our offspring.

Genetic determinants of complex phenotypes

In later years we have been involved in the identification of hundreds of genetic variants influencing the risk of common diseases through genome-wide association studies (GWAS). Despite this success, only a small fraction of the genetic contribution to disease has been identified, and most of the genetic factors remain unknown.

This “missing heritability” might be explained by the contribution of rare and population specific single nucleotide polymorphisms (SNPs), which are underrepresented in GWAS. In this project I study the contribution of rare and population specific SNPs to the etiology of human traits.

Mendelian randomization

Biomarkers have been identified for many diseases, and might serve as potential drug targets. Mendelian randomization can be used to evaluate the causal effect of the biomarkers on disease risk and progress. In a Mendelian randomization study, a genetic variant, that increases the levels of a biomarker, is used to divide a population into genotypic subgroups, in an analogous way to how participants are divided into arms in a randomized clinical trial.

The aim of this project is to use Mendelian randomization to evaluate the causal effect of biomarkers on risk of disease, and on disease progress.