Category Archives: Transhuman News

Dr. Anthony Komaroff/Universal Uclick

In last week's column, a reader asked whether she should be tested for genes linked to Alzheimer's disease. Today, I thought I'd give you my view on the larger question: Will studies of our genes change the practice of medicine and improve our lives?

My answer: During my career, progress in human genetics has been greater than virtually anyone imagined. However, human genetics also has turned out to be much more complicated than people imagined. As a result, we have not moved as rapidly as we had hoped in changing medical practice.

I graduated from medical school in the late 1960s. We knew what human genes were made of -- DNA -- and we were beginning to understand how genes work. We had even identified a handful of genes that were linked to specific diseases. We assumed that disease resulted from an abnormality in the structure of a gene.

If I had asked any biologist on the day I graduated, Will we ever know how many genes we have, and the exact structure of each gene? I'll bet the answer would have been: Not in my lifetime, or my children's lifetime.

They would have been wrong. Today we do know those answers. Indeed, some diseases are caused by an abnormality in the structure of genes. In fact, sometimes it is very simple: one particular change at one particular spot in just one particular gene leads to a specific disease. Sickle cell anemia is an example.

Unfortunately, with most diseases it's far from that simple. The first complexity: Most diseases are influenced by the structure of multiple genes, not just one. Examples are diabetes and high blood pressure.

The second complexity: Many diseases are explained not by an abnormal gene structure, but by whether genes are properly turned on or off. Most cancers fall into this category.

What do I mean by that? Every cell in our body has the same set of genes. Yet, a cell in our eye that sees light is different from a cell in our stomach that makes acid. Why? Because different genes are turned on in each type of cell.

Similarly, if a gene with a normal structure is not properly turned on or off, a cell can malfunction -- it can become diseased. Whether a gene is turned on properly is proving to be a more important cause of disease than we once imagined.

Link:
ASK DOCTOR K: Progress in genetics will lead to better diagnosis

Details Published on Tuesday, 25 February 2014 16:53

Hardened plaque discovered on the teeth of 1,000 year old human skeletons has revealed not only their diets but the diseases they faced.HARDENED plaque discovered on the teeth of 1,000-year-old human skeletons has revealed the world's oldest case of gum disease.

Described as a 'microbial Pompeii', the plaque preserved bacteria and microscopic particles of food on the surfaces of teeth, effectively creating a mineral tomb for microbiomes.

And it revealed that our ancestors had gum disease that was caused by the same bacteria that plagues modern man, despite major changes in diet and hygiene.

They found that the ancient human oral microbiome already contained the basic genetic machinery for antibiotic resistance over eight centuries before the invention of antibiotics in the 1940s.

DNA testing of the tartar also showed some of the things ancient humans had been eating, such a vegetables, which do not show up in fossil records.

Gum disease is caused by a build-up of plaque on the teeth and is thought to affect over half of adults in the UK.

The teeth were taken from skeletons found at a site in Dalheim, Germany.Plaque is a sticky substance that contains bacteria and when it hardens it forms tartar.

Unlike bone, which rapidly loses much of its molecular information when buried, calculus grows slowly in the mouth and enters the soil in a much more stable state, helping it to preserve biomolecules.

Researchers from the University of York, along with Swiss and Danish colleagues, said studying plaque will be more important than teeth in discovering the lifestyles of our past ancestors.

Read the original here:
Plaque On 1000-Year-Old Human Teeth Could Unlock Secrets Of Medieval Diet And Disease