The domestication of the Eurasian grape ( Vitis vinifera ssp. sativa ) from its wild ancestor ( Vitis vinifera ssp. sylvestris ) has long been claimed to have occurred in Transcaucasia where its greatest genetic diversity is found and where very early archaeological evidence, including grape pips and artefacts of a 'wine culture', have been excavated. Whether from Transcaucasia or the nearby Taurus or Zagros Mountains, it is hypothesized that this wine culture spread southwards and eventually westwards around the Mediterranean basin, together with the transplantation of cultivated grape cuttings. However, the existence of morphological differentiation between cultivars from eastern and western ends of the modern distribution of the Eurasian grape suggests the existence of different genetic contribution from local sylvestris populations or multilocal selection and domestication of sylvestris genotypes. To tackle this issue, we analysed chlorotype variation and distribution in 1201 samples of sylvestris and sativa genotypes from the whole area of the species' distribution and studied their genetic relationships. The results suggest the existence of at least two important origins for the cultivated germplasm, one in the Near East and another in the western Mediterranean region, the latter of which gave rise to many of the current Western European cultivars. Indeed, over 70% of the Iberian Peninsula cultivars display chlorotypes that are only compatible with their having derived from western sylvestris populations.

Using reverse transcriptase-amplified fragment length polymorphism (RT-AFLP) analysis of differential mRNA expression and semiquantitative reverse transcriptase-polymerase chain reaction, we compared mRNA expression in bovine blastocysts from 4 sources, known to differ in quality in terms of their ability to withstand cryopreservation: 1) in vitro culture in synthetic oviduct fluid of in vitro-matured (IVM)/in vitro fertilized (IVF) zygotes; 2) in vitro culture in TCM-199 supplemented with granulosa cells (coculture) of IVM/IVF zygotes; 3) in vivo culture in the ewe oviduct of IVM/IVF zygotes; or 4) superovulation, artificial insemination, and nonsurgical embryo recovery. Total mRNA was isolated from pools of blastocysts and reverse transcription was performed. Triplicate reactions from each sample were displayed, and only consistent banding variations were recorded. Using AFLP-differential display assay, we found that cDNA banding patterns are highly conserved between the 4 groups of blastocysts studied; however, there was a difference of 7% in bands either missing or expressed across the groups. Fifty bands were reamplified, and a sequence comparison search revealed similarity of 14 isolated fragments to ribosomal and mitochondrial genes, 16 matched to described cDNA, and 20 corresponded to unknown sequences that may represent novel genes. The study of 7 differentially expressed mRNAs known to be involved in developmental process in the embryo suggests roles for apoptosis, oxidative stress, gap junctions, and differentiation in the determination of embryo quality. The aberrant transcription patterns detected in in vitro-produced bovine embryos compared with those produced in vivo may explain their reduced quality in terms of viability after cryopreservation.

The wild grapevine, Vitis vinifera L. ssp. sylvestris (Gmelin) Hegi, considered as the ancestor of the cultivated grapevine, is native from Eurasia. In Spain, natural populations of V. vinifera ssp. sylvestris can still be found along river banks. In this work, we have performed a wide search of wild grapevine populations in Spain and characterized the amount and distribution of their genetic diversity using 25 nuclear SSR loci. We have also analysed the possible coexistence in the natural habitat of wild grapevines with naturalized grapevine cultivars and rootstocks. In this way, phenotypic and genetic analyses identified 19% of the collected samples as derived from cultivated genotypes, being either naturalized cultivars or hybrid genotypes derived from spontaneous crosses between wild and cultivated grapevines. The genetic diversity of wild grapevine populations was similar than that observed in the cultivated group. The molecular analysis showed that cultivated germplasm and wild germplasm are genetically divergent with low level of introgression. Using a model-based approach implemented in the software structure, we identified four genetic groups, with two of them fundamentally represented among cultivated genotypes and two among wild accessions. The analyses of genetic relationships between wild and cultivated grapevines could suggest a genetic contribution of wild accessions from Spain to current Western cultivars.

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