Genetic Link Between Modern Wine Grapes and Ancient Varieties Found in International Study

A new study led by the Paleontology Lab at the Steinhardt Museum of Natural History at Tel Aviv University and Haifa University analyzed DNA from ancient local grape seeds unearthed in archaeological excavations in the Negev.

One seed nearly identical to the Syriki variety used today to make high-quality red wines was found in Greece and Lebanon, while another seed, close to the white variety called Be’er, was found still growing in abandoned vineyards in the dunes. Palmach.

Exported to Europe

The genetic study was led by Dr. Pnina Cohen and Dr. Merav Miri of the Paleontology Laboratory at the Steinhardt Museum of Natural History at Tel Aviv University. The seeds were found in an archaeological excavation led by Professor Guy Bar Oz of the Faculty of Archeology and Maritime Cultures at the University of Haifa, in collaboration with researchers from the Israel Antiquities Authority. Other participants included researchers from the University of Haifa, the Weizmann Institute, Bar-Ilan University, and research institutions in France, Denmark, and the United Kingdom. The research is published in the journal. Proceedings of the National Academy of Sciences.

“Archaeological excavations carried out in the Negev (in Israel) in recent years have revealed a flourishing wine industry from the early Byzantine and Arab period (around the 4th to the 9th centuries AD), particularly at the sites of Shivta, Halusa, Avdat, and Nizana, which were large and flourishing cities in That time,” says Professor Jay Bar Oz of the University of Haifa.

“The findings include large presses, jugs for the exclusive storage of wine, exported to Europe, and grape seeds preserved for more than a thousand years. This industry gradually declined after the Islamic conquest in the seventh century, as Islam prohibited the consumption of wine.”

“The cultivation of wine grapes in the Negev has only been renewed in modern times, in the State of Israel, mostly since the 1980s. However, this industry relies mainly on grape varieties imported from Europe.”

DNA extraction

One particularly interesting find was a large hoard of grape seeds, discovered on the floor of a locked room in Avdat. The researchers explain that these seeds have been relatively well preserved thanks to protection from weather events such as temperature extremes, floods or droughts. To learn more about the seeds, and in hopes of discovering which species they might belong to, the researchers prepared to extract their DNA at a paleobiology lab.

“Paleogenomics uses a range of advanced techniques to analyze ancient genomes, mainly from archaeological finds,” explains Dr. Merry of Tel Aviv University’s Steinhardt Museum of Natural History.

“Because the DNA molecule is so delicate and breaks down over time, especially under high temperatures, we usually get only small pieces of DNA, often in poor preservation. To protect them, we work under special conditions: a biology lab The old insulated lab is clean, with positive air pressure that keeps contaminants away, and we get it into sterile “spacesuits” familiar to everyone from the COVID pandemic.”

First, the researchers looked for any remaining organic matter in the seeds. For this, they used FTIR (Fourier transform infrared spectroscopy) – a chemical technique that uses infrared light to produce a spectrum of light that identifies the content of a sample. The researchers found traces of organic material in 16 of the seeds, and have continued to extract DNA from these samples.

Ancient Grapes: Still Existing Today

The extracted DNA was sequenced, focusing on about 10,000 genomic sites where diversity-specific features are normally located, and the results were compared with databases of modern vineyards from around the world: in 11 samples, the quality of the germplasm was too poor to allow any definite conclusions. Three of the remaining specimens have been identified as generally belonging to local taxa. Finally, the two specimens of the highest quality, both from about AD 900, have been identified as belonging to certain local taxa that still exist today.

The discovery was unusual:

• A single seed was found belonging to Syriki, a well-known Middle Eastern variety with a long history of cultivation in the southern Levant and Crete, and is still used today to make high-quality red wines in Greece (where it is known to have arrived from the East) and in Lebanon. Since wine grapes are usually named after the place of their origin, it is entirely possible that the name Syriki derives from the Nahal Sorek, an important stream in the Judean hills. Moreover, this diversity may appear in the Bible – in Jacob’s blessing of his son Judas: “He will tie his donkey to the vine, and the colt to the chosen bough (surica), and wash his clothes in wine, and his clothes in the blood of grapes (Gen. 49, 11); and perhaps suggest Also in the giant bunch of grapes brought back by the men sent by Moses to explore the land: “When they come to the Valley of Eshkol (some know them as Nahal Sorek) they cut down a bough bearing a single bunch of grapes. Two of them carried him on a pole between them ”(Numbers 13, 23).
• Other high-quality seeds have been identified as related to Bir, a white wine grape still growing in the Palmachim sands on Israel’s seashore, in the remains of vineyards that may have been abandoned in the mid-20th century. For the first time ever, researchers were able to use the genome of a grape seed to determine the color of the fruit, discovering that it was actually a white grape—the oldest botanical specimen of a white variety ever identified. Well, a unique local variety, endemic to the Land of Israel, is used today by Barkan Winery to make its own white wine.

Small items tell a big story

“The cool thing about paleobiology is that sometimes, little things can tell a big story,” says Dr. Merry. “That is exactly what happened in this study. With a little bit of DNA extracted from two grape seeds, we were able to trace the continuity of the local wine industry—from the Byzantine period, over a thousand years ago, to the present day.”

“We believe that our findings are also important for the modern wine industry in Israel, which has grown and flourished in recent decades. Today, most of the varietals grown here were imported from Europe, so the local conditions are not ideal for them. Local varietals could be better suited to the local climate.” and soils, especially in the desert region of the Negev. Our study opens up new pathways for restoring and improving ancient local varieties, to create wine grapes that are better suited to challenging climatic conditions such as high temperatures and little rain.”