Posted on September 7, 2021
This came out of a study published in Science.
They looked at expression of more than 35,000 genes in 44 types of tissue from 858 donors as part of the NIH Genotype Tissue Expression Project. Why did they do this study? There are implications in medicine.
- There are XX vs XY differences in how genes affect how a person metabolizes medication. Many studies are done only on XY mice, and this may affect considerations for XX patients. This can affect mechanism of action and dosages.
- There are links to traits, including birth weight, blood pressure, cholesterol levels, breast cancer, and body fat. They found links between XX and breast cancer and autoimmune conditions like inflammatory bowel disease. They found higher gene expression in XY with baldness and body fat.
Findings?
- Subtle difference in gene expression through the tissues
- These differences were specific to each tissue type.
- These differences were due to transcription factors- the genes that control expression of other genes
- 58 new genotype specific links with traits were identified.
- One of the two X chromosomes in XX genotype is silenced in each cell to help balance gene expression, but some genes on the X chromosome escape inactivation in females.
- They are hoping this will lead to new approaches to personalize care for cancer that take genotypes into account.
My thoughts?
The more we understand about how the body works, the more we can tailor treatments to each individual. I think we are barely scratching the surface with what we know about how the human body works. I find all of this fascinating. Throughout my training as a doctor, I marvel at the intricacy of the human body- the organs, the individual cells, the nucleus, how we are able to give birth and fight infection and heal a surgical wound.