Björn Reinius

Project summary

Determining the in vivo end states of X-chromosome inactivation

Women’s cells contain two copies of the X chromosome, while men’s cells contain only one. To balance the expression of genes encoded on the X chromosome, gene activity from one of the two X chromosomes is silenced in female cells. This phenomenon, known as X-chromosome inactivation, is an important area of research in developmental and cell biology. As a result, the female body consists of a “mosaic” of cells in which either the maternal or paternal copy of the X chromosome is active.

 

Cell biology research has shown that some genes on the silenced X chromosome escape inactivation and continue to produce gene products even though surrounding genes on the X chromosome have been switched off. By studying these genes, we can learn more about the fundamental molecular mechanisms that regulate gene activity, as well as diseases associated with defective regulation of the X chromosome.

 

Recent research has also shown that the exact set of genes that escape X-chromosome inactivation differs between cell types in the body, but how and why this occurs remains unknown. This research programme will map X-chromosome inactivation in detail across different tissues and cell types.

 

The aim of this fundamental research is to uncover the cellular and molecular mechanisms that regulate gene activity. This knowledge is important for understanding how genetic programmes can be modified in different cell types and why diseases caused by defective genes on the X chromosome can vary in their course and severity.