International Grape Genome Program
Encyclopedia
Genome project
Genome projects are scientific endeavours that ultimately aim to determine the complete genome sequence of an organism and to annotate protein-coding genes and other important genome-encoded features...
dedicated to determining the genome sequence of the grape
Grape
A grape is a non-climacteric fruit, specifically a berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or they can be used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, molasses and grape seed oil. Grapes are also...
vine Vitis vinifera
Vitis vinifera
Vitis vinifera is a species of Vitis, native to the Mediterranean region, central Europe, and southwestern Asia, from Morocco and Portugal north to southern Germany and east to northern Iran....
. It is a multinational project involving research centers in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, Chile
Chile
Chile ,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...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
, and the United States
United States
The 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 fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
, its biology
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
is still poorly understood. Many centuries of viticulture
Viticulture
Viticulture 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 environment
Natural environment
The natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species....
and deals with abiotic stresses, pests and disease
Disease
A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...
s is currently unknown.
Agricultural technology surrounding Vitis has been traditionally based upon specific genotype
Genotype
The genotype is the genetic makeup 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 yield
Crop yield
In agriculture, crop yield is not only a measure of the yield of cereal per unit area of land under cultivation, yield is also the seed generation of the plant itself...
. 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 viticulture
Viticulture
Viticulture 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 grape
Grape
A grape is a non-climacteric fruit, specifically a berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or they can be used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, molasses and grape seed oil. Grapes are also...
characteristics and quality in a predictable way.
Initial discoveries
As of March 2007, the project has mapped over half of the grapevine genome. In the course of their research, the Cooperative Research CentreCooperative Research Centre
Cooperative 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 CSIRO
Commonwealth Scientific and Industrial Research Organisation
The Commonwealth Scientific and Industrial Research Organisation is the national government body for scientific research in Australia...
Plant Industry Horticulture Unit in Adelaide
Adelaide
Adelaide is the capital city of South Australia and the fifth-largest city in Australia. Adelaide has an estimated population of more than 1.2 million...
, 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 genes
Gênes
Gênes is the name of a département of the First French Empire in present Italy, named after the city of Genoa. It was formed in 1805, when Napoleon Bonaparte occupied the Republic of Genoa. Its capital was Genoa, and it was divided in 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 anthocyanin
Anthocyanin
Anthocyanins are water-soluble vacuolar pigments that may appear red, purple, or blue according to pH...
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 biosynthesis
Biosynthesis
Biosynthesis 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 transcribe
Transcription (genetics)
Transcription is the process of creating a complementary 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 by the action of the correct enzymes...
d in white grape berries. The white berry allele
Allele
An allele is one of two or more forms of a gene or a genetic locus . "Allel" is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation...
of VvMYBA2 was inactivated by two mutations, one leading to an amino acid
Amino acid
Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
substitution and the other to a frameshift mutation. Tests showed that either mutation removes the ability of the regulator
Regulator gene
A regulator gene, regulator, or regulatory gene is a gene involved in controlling the expression of one or more other genes. A regulator gene may encode a protein, or it may work at the level of RNA, as in the case of genes encoding microRNAs....
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 cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
s tested contained the white berry allele, but not red berry alleles - and all displayed exactly the same double mutation, pointing to a single, common ancestor
Ancestor
An 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 Egypt
Ancient Egypt
Ancient Egypt was an ancient civilization of Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh...
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 Rioja
Rioja (wine)
Rioja 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 Alta, Rioja...
, Spain, noticed a white grape mutation in some Tempranillo
Tempranillo
Tempranillo 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 propagated
Plant propagation
Plant propagation is the process of creating new plants from a variety of sources: seeds, cuttings, bulbs and other plant parts. Plant propagation can also refer to the artificial or natural dispersal of plants.-Sexual propagation :...
and the mutation did not revert, the new varietal
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
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.