A single cell can contain all the information that is needed to build a human being. These instructions that tell a body how to develop are called genes. Genes are part of DNA.
The study of genes is called genetics. Genetics have fascinated the medical community ever since genes were first discovered.
Your genes are packed inside bundles called chromosomes. Your cells have 46 chromosomes, or 26 pairs. Each gene group that makes up a single chromosome is partnered with its other paired chromosome.
Your gene pairs have different forms. One pair may give identical instructions, or it may give different instructions.
For example, one gene (of the gene pair) may order brown eyes, while the other may order blue eyes. One gene may be dominant, and the other may be recessive. In this case the gene ordering brown eyes is dominant, so your eye color would be brown.
Geneticists are very interested in the study of recessive genes, because many diseases are caused by recessive genes. If someone has the pair of genes which cause cystic fibrosis, they will get the disease.
Researchers have now discovered that factors that modify the function of DNA but don’t change its sequence are a major player in disease.
Normally, these factors that influence DNA are beautifully coordinated. Portions of a chromosome that are packed in just the right way have the highest amount of gene expression.
When these chromosomes are too loosely or tightly put together, they can change how a gene works — usually in the form of a mutation. “In cancer cells, this happens in 20% of our genes,” said lead researcher Dr. Anindya Dutta.
The researchers are thrilled at this new understanding about chromosomes and gene expression. They are confident that it may lead to a much more specific method of identifying disease risk.
This study is part of the ENCODE Project — the Encyclopedia of DNA elements. The project involves 35 groups from 80 organizations worldwide.
The ENCODE team wants to study what has been called “junk DNA.” Only 1.5 % of the genome actually makes cellular proteins involved in the building blocks of life. What, the researchers wondered, does the other 98.5% do?
So far, they’ve discovered this link between the way chromosomes are packed together and the risk for disease. The researchers admit that it will take some time to figure out exactly what the mechanism of disease risk is. But they are very hopeful that more discoveries are on the way.