Thursday, October 16, 2008

Earliest confirmed TB case found


The 9,000-year-old remains of a mother and her baby discovered off the coast of Israel provide the earliest concrete evidence of human TB, say researchers.



TB skeletonThe bones were excavated from Alit-Yam, an ancient Neolithic village near Haifa, which has been submerged in the Mediterranean for thousands of years.

The experts from University College London and Tel-Aviv University used DNA technology to confirm the bacterium.

Others have found remains that hint at TB dating from about 500,000 years ago.

However, there is no firm proof that the tell tale signs seen in the skeleton of a young man believed to belong to the first human species to migrate out of Africa - Homo erectus - were in fact caused by TB. Some experts doubt it.

Watery grave

The Israel bones, discovered by Dr Helen Donoghue and Dr Mark Spigelman, prove the disease is at least 3,000 years older than previously confirmed in other remains found in Italy. The watery grave provided the ideal environment to preserve the skeleton and its DNA. ...

The scientists were also able to show that the DNA of the strain of TB in the skeletons had lost a particular piece of DNA which is characteristic of a common family of strains present in the world today.

"The fact that this deletion had occurred 9,000 years ago gives us a much better idea of the rate of change of the bacterium over time, and indicates an extremely long association with humans," said Dr Donoghue. - bbc

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