Compiling a Worldwide Genetic Atlas

Just amazing: tracing the genetic legacy of Alexander the Great in Central Asia, among many, many others:

Dr. Myers and his colleagues have detected European ancestry that entered the Tu people of central China between the 11th and 14th centuries; this, they surmise, could be from traders traveling the Silk Road. They find among Northern Italians an insertion of Middle Eastern DNA that occurred between 776 B.C. and A.D. 550, and may represent the Etruscans, a mysterious people said by the ancient Greek historian Herodotus to have emigrated from Lydia in Turkey.

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RIP Frederick Sanger

There’s a fascinating obituary for Frederick Sanger in today’s New York Times. If you’re at all interested in biochemistry, amino acids, or DNA sequencing it’s worth a read:

Dr. Sanger stayed on at Cambridge and soon became immersed in the study of proteins. When he started his work, scientists knew that proteins were chains of amino acids, fitted together like a child’s colorful snap-bead toy. But there are 22 different amino acids, and scientists had no way of determining the sequence of these amino acid “beads” along the chains.

Dr. Sanger decided to study insulin, a protein that was readily available in a purified form since it is used to treat diabetes. His choice of insulin turned out to be a lucky one — with 51 amino acids, insulin has a relatively simple structure. Nonetheless, it took him 10 years to unlock its chemical sequence.

His approach, which he called the “jigsaw puzzle method,” involved breaking insulin into manageable chunks for analysis and then using his knowledge of chemical bonds to fit the pieces back together. Using this technique, scientists went on to determine the sequences of other proteins. Dr. Sanger received the Nobel just four years after he published his results in 1954.

He later won a second Nobel for the DNA-decoding process that was named after him.

According to the obit he lived in Swaffham Bulbeck, surely in the Top Ten of English village names.