Xist ribonucleoproteins promote female sex-biased autoimmunity. (https://pubmed.ncbi.nlm.nih.gov/38306984/)

These scientists wanted to understand why autoimmune diseases, which are when the body's immune system attacks itself, affect girls more than boys. They knew that a special part of the girls' chromosomes, called the XX chromosomes, was connected to this. They also knew that a molecule called Xist, which is only found in girls, helps to turn off one of the X chromosomes so that girls have the same amount of genes as boys.

To study this, the scientists did some experiments with mice. They made some male mice that had the Xist molecule in them, just like the girls. They found that these mice started making antibodies, which are special proteins that help fight off infections, just like in autoimmune diseases. They also saw that these mice had more problems with their organs when they were given a substance that causes lupus, which is a type of autoimmune disease.

The scientists also looked at human patients with autoimmune diseases and found that they had antibodies to the Xist molecule. This means that the Xist molecule is involved in causing autoimmune diseases in both mice and humans.

So, the scientists discovered that the Xist molecule, which is only found in girls, plays a big role in causing autoimmune diseases. It helps to create a special group of proteins that are involved in the immune system, and this can lead to the body attacking itself. This is why autoimmune diseases affect girls more than boys.

Dou DR., Zhao Y., Belk JA., Zhao Y., Casey KM., Chen DC., Li R., Yu B., Srinivasan S., Abe BT., Kraft K., Hellstrom C., Sjoberg R., Chang S., Feng A., Goldman DW., Shah AA., Petri M., Chung LS., Fiorentino DF., Lundberg EK., Wutz A., Utz PJ., Chang HY. Xist ribonucleoproteins promote female sex-biased autoimmunity. Cell. 2024 Feb 1;187(3):733-749.e16. doi: 10.1016/j.cell.2023.12.037.