The
International Grape Genomics Program (
IGGP) is a collaborative
genome projectGenome projects are scientific endeavours that ultimately aim to determine the complete genome sequence of an organism . The genome sequence for any organism requires the DNA sequences for each of the chromosomes in an organism to be determined...
dedicated to determining the genome sequence of the
grapeA grape is the non-climacteric fruit, botanically a true berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, and grape seed oil...
vine
Vitis viniferaFor the town in Australia, see Vinifera, VictoriaVitis vinifera is a species of Vitis, native to the Mediterranean region, central Europe, and southwestern Asia, from Morocco and Spain north to southern Germany and east to northern Iran.It is a liana growing to 35 m tall, with flaky bark...
. It is a multinational project involving research centers in
AustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the continental mainland , the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans...
,
FranceFrance , officially the French Republic , is a country located in Western Europe, with several overseas islands and territories located on other continents. Metropolitan France extends from the Mediterranean Sea to the English Channel and the North Sea, and from the Rhine to the Atlantic Ocean...
,
CanadaCanada is a country occupying most of northern North America, extending from the Atlantic Ocean in the east to the Pacific Ocean in the west and northward into the Arctic Ocean...
,
ChileChile, officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
,
GermanyGermany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium,...
,
ItalyItaly , officially the Italian Republic , is a country located on the Italian Peninsula in Southern Europe and on the two largest islands in the Mediterranean Sea, Sicily and Sardinia. Italy shares its northern, Alpine boundary with France, Switzerland, Austria and Slovenia...
,
South AfricaThe Republic of South Africa is a country located at the southern tip of Africa, with a coastline on the Atlantic and Indian Oceans. To the north lie Namibia, Botswana and Zimbabwe, to the east are Mozambique and Swaziland, while Lesotho is an independent country surrounded by South Africa.Modern...
,
SpainSpain , officially the Kingdom of Spain , is a country located in southwestern Europe on the Iberian Peninsula.
[The Spanish constitution does not establish any official denomination of the country, even though España , Estado español and Nación española are used interchangeably...]
, and the
United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
The project was initiated in on the premise that whereas the
Vitis family provides the world's most economically important
fruitThe term fruit has different meanings dependent on context, and the term is not synonymous in food preparation and biology. Fruits are the means by which flowering plants disseminate seeds, and the presence of seeds indicates that a structure is most likely a fruit, though not all seeds come from...
, its
biologyBiology is the natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy...
is still poorly understood.
The
International Grape Genomics Program (
IGGP) is a collaborative
genome projectGenome projects are scientific endeavours that ultimately aim to determine the complete genome sequence of an organism . The genome sequence for any organism requires the DNA sequences for each of the chromosomes in an organism to be determined...
dedicated to determining the genome sequence of the
grapeA grape is the non-climacteric fruit, botanically a true berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, and grape seed oil...
vine
Vitis viniferaFor the town in Australia, see Vinifera, VictoriaVitis vinifera is a species of Vitis, native to the Mediterranean region, central Europe, and southwestern Asia, from Morocco and Spain north to southern Germany and east to northern Iran.It is a liana growing to 35 m tall, with flaky bark...
. It is a multinational project involving research centers in
AustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the continental mainland , the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans...
,
FranceFrance , officially the French Republic , is a country located in Western Europe, with several overseas islands and territories located on other continents. Metropolitan France extends from the Mediterranean Sea to the English Channel and the North Sea, and from the Rhine to the Atlantic Ocean...
,
CanadaCanada is a country occupying most of northern North America, extending from the Atlantic Ocean in the east to the Pacific Ocean in the west and northward into the Arctic Ocean...
,
ChileChile, officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
,
GermanyGermany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium,...
,
ItalyItaly , officially the Italian Republic , is a country located on the Italian Peninsula in Southern Europe and on the two largest islands in the Mediterranean Sea, Sicily and Sardinia. Italy shares its northern, Alpine boundary with France, Switzerland, Austria and Slovenia...
,
South AfricaThe Republic of South Africa is a country located at the southern tip of Africa, with a coastline on the Atlantic and Indian Oceans. To the north lie Namibia, Botswana and Zimbabwe, to the east are Mozambique and Swaziland, while Lesotho is an independent country surrounded by South Africa.Modern...
,
SpainSpain , officially the Kingdom of Spain , is a country located in southwestern Europe on the Iberian Peninsula.
[The Spanish constitution does not establish any official denomination of the country, even though España , Estado español and Nación española are used interchangeably...]
, and the
United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
The project was initiated in on the premise that whereas the
Vitis family provides the world's most economically important
fruitThe term fruit has different meanings dependent on context, and the term is not synonymous in food preparation and biology. Fruits are the means by which flowering plants disseminate seeds, and the presence of seeds indicates that a structure is most likely a fruit, though not all seeds come from...
, its
biologyBiology is the natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy...
is still poorly understood. Many centuries of
viticultureViticulture is the science, production and study of grapes which deals with the series of events that occur in the vineyard. When the grapes are used for winemaking, it is also known as viniculture...
have provided a large number of well-informed wine-producing centres throughout the world, yet exactly how a grapevine plant responds and interacts with the physical
environmentThe natural environment, commonly referred to simply as the environment, is a term that encompasses all living and non-living things occurring naturally on Earth or some region thereof....
and deals with abiotic stresses, pests and
diseaseA disease or medical condition isan abnormal condition of an organism that impairs bodily functions, associated with specific symptoms and signs...
s is currently unknown.
Agricultural technology surrounding
Vitis has been traditionally based upon specific
genotypeThe genotype is the genetic constitution of a cell, an organism, or an individual usually with reference to a specific character under consideration...
s, which in the main have relied on "vegetative multiplication" and control of growing conditions to improve quality and
yieldIn agriculture, crop yield is not only a measure of the yield of cereal per unit area of land under cultivation, it is also the seed generation of the plant itself, i.e. one grain of wheat produces a stalk yielding three grain, or 1:3...
. While advances in quality have certainly been achieved, it has involved increased costs and is in danger of incurring unsustainable environmental overheads. The argument is that the relatively unknown biology of
Vitis is capable of delivering desired viticultural improvements without the associated ongoing costs, and establishing its genome sequence will examine the role individual genes play in
viticultureViticulture is the science, production and study of grapes which deals with the series of events that occur in the vineyard. When the grapes are used for winemaking, it is also known as viniculture...
, improving
grapeA grape is the non-climacteric fruit, botanically a true berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, and grape seed oil...
characteristics and quality in a predictable way.
Initial discoveries
As at March 2007, the project has mapped over half of the grapevine genome. In the course of their research, the
Cooperative Research CentreCooperative Research Centres are key bodies for Australian scientific research. The Cooperative Research Centres Program was established in 1990 to enhance Australia's industrial, commercial and economic growth through the development of sustained, user-driven, cooperative public-private research...
for Viticulture (CRCV), based at the
CSIROThe Commonwealth Scientific and Industrial Research Organisation is the national government body for scientific research in Australia...
Plant Industry Horticulture Unit in
AdelaideAdelaide is the capital and most populous city of the Australian state of South Australia, and is the fifth-largest city in Australia, with a population of more than 1.1 million. It is a coastal city situated on the eastern shores of Gulf St. Vincent, on the Adelaide Plains, north of the Fleurieu...
, Australia (one of the IGGP collaborating centres) discovered that white grapes only exist today as a result of a rare genetic mutation which took place thousands of years ago. White grapes are believed to have arisen due to the extremely rare and independent mutation of two similar and adjacent regulatory
genesGênes is the name of a département of the First French Empire in present Italy. It was named after the city Genoa. It was formed in 1805, when Napoleon Bonaparte occupied the Republic of Genoa. Its capital was Genoa. It was divided into the arrondissements of Genoa, Bobbio, Novi Ligure, Tortona and...
,
VvMYBA1 and
VvMYBA2, in a red grape parent.
Most grapevine cultivars can be divided into two groups - red and white - based on the presence or absence of
anthocyaninAnthocyanins are water-soluble vacuolar pigments that may appear red, purple, or blue according to pH. They belong to a parent class of molecules called flavonoids synthesized via the phenylpropanoid pathway; they are odorless and nearly flavorless, contributing to taste as a moderately stringent...
in the skin of the fruit, which the geneticists discovered to be controlled by these two genes. Although either can dictate colour, the
VvMYBA1 gene, which activates the anthocyanin
biosynthesisBiosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step...
necessary to produce red grapes, was shown not to be
transcribeTranscription, or RNA synthesis, is the process of creating an equivalent RNA copy of a sequence of DNA. Both RNA and DNA are nucleic acids, which use base pairs of nucleotides as a complementary language that can be converted back and forth from DNA to RNA in the presence of the correct enzymes...
d in white grape berries. The white berry
alleleAn allele is one of a series of different forms of a gene. The word is a short form of allelomorph , which was used in the early days of genetics to describe variant forms of a gene detected as different phenotypes...
of
VvMYBA2 was inactivated by two mutations, one leading to an
amino acidAmino acids are molecules containing an amine group, a carboxylic acid group and one of the twenty R-groups. These molecules are particularly important in biochemistry, where this term refers to alpha-amino acids with the general formula H
2NCHRCOOH, where R is an organic substituent...
substitution and the other to a
frameshiftA directed change in translational reading frames that allows the production of a single protein from two or more overlapping genes. The process is programmed by the nucleotide sequence of the mRNA and is sometimes also affected by the secondary or tertiary mRNA structure...
mutation. Tests showed that either mutation removes the ability of the
regulatorRegulator may refer to:*Regulator , a device which has the function of maintaining a designated characteristic*Battery regulator, a device in a battery pack which bleeds off excess charge current to let all cells reach full charge without overcharging some cells*Diving regulator, which provides a...
to switch on anthocyanin biosynthesis, and when both are switched off it results in a white cultivar. Sequence analyses of the
VvMYBA2 gene confirmed that all of the 55 white cultivars tested contained the white berry allele, but not red berry alleles - and all displayed the exact same double mutation, pointing to a single, common
ancestorAn ancestor is a parent or the parent of an ancestor ....
. Assuming this to be true of all white cultivars, without this single parent vine there would be no white grapes today. White wine residues discovered in
ancient EgyptAncient Egypt was an ancient civilization of eastern North Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. The civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh, and...
ian pottery remains suggest that this mutation occurred at least three thousand years ago, although in lieu of testing against a known white grape genome, the possibility remains that the mutation could have occurred more recently.
A similar dual mutation occurred during the last decade. Viticultor Jesús Galilea Esteban, of the vineyard Murillo de Rio Leza in
RiojaRioja is a wine, with Denominación de Origen Calificada named after La Rioja, in Spain. Rioja is made from grapes grown not only in the Autonomous Community of La Rioja, but also in parts of Navarre and the Basque province of Álava. Rioja is further subdivided into three zones: Rioja Alavesa,...
, Spain, noticed a white grape mutation in some
TempranilloTempranillo is a variety of black grape widely grown to make full-bodied red wines in its native Spain. It is the main grape used in Rioja, and is often referred to as Spain's "noble grape". Its name is the diminutive of the Spanish temprano , a reference to the fact that it ripens several weeks...
grapevines growing on his estate. After the white vine was
propagatedPlant propagation is the process of artificially or naturally distributing plants.-Sexual propagation :Seeds and spores can be used for reproduction . Seeds are typically produced from sexual reproduction within a species, since because genetic recombination has occurred plants grown from seed may...
and the mutation did not revert, the new
varietal"Varietal" describes wines made primarily from a single named grape variety, and which typically displays the name of that variety on the wine label. Examples of grape varieties commonly used in varietal wines are Cabernet Sauvignon, Chardonnay and Merlot...
was granted outline permission to apply for approved grape status by the Rioja
D.O.Denominación de Origen is part of a regulatory classification system primarily for Spanish wines but also for other foodstuffs like honey, meats and condiments. In wines it parallels the hierarchical system of France and Italy although Rioja and Sherry preceded the full system...
and the first hectare of white Tempranillo was planted in the region in the year 2000. Both white and red vines share identical leaves, clusters and berry shape, as well as the short ripening cycles and sensitivity to pests and diseases typical of the red Tempranillo. The mutation is thought to have occurred as a result of environmental factors.