Selective extract from the genetic information pattern of the entire genome - the DNA chains of the chromosomes. This extract plays a decisive role in the determination of grape varieties within the framework of molecular genetics. Due to the immense volume of genetic information, we concentrate on a few selected extracts. Their information content can then be combined to form a "genetic fingerprint", which can be used to characterise varieties by genotype and, once defined, to re-identify them. In contrast, previously only the phenotype could be used for this purpose. This represents only external, visually recognisable characteristics such as berry colour, berry shape and the shape of the leaves. See also under vine systematics.