FIELD: genetic engineering, medicinal genetics. SUBSTANCE: invention relates to the construction of the novel molecular-genetic marker of human 18-th chromosome showing specificity to centromere region of this chromosome. This marker is the recombinant plasmid DNA pYAI 960. DNA has Pst I-Pst I DNA-fragment of vector pUC 19 (size is 2700 nucleotide pairs), -Pst I-Pst I alphoid-like DNA-fragment of human lymphocytes showing the high specificity for centromere region of human 18-th chromosome (size is 1400 nucleotide pairs) with two internal unique Eco RI-restriction sites and genetic marker: Ampr - resistance gene to ampicillin. Invention provides to identify chromosome 18 in interphase and metaphase cells in prenatal diagnosis and clinical cytogenetics effectively and to refine the diagnosis (to identify breakage points in anomal chromosomes) in patients with chromosomal pathology also. EFFECT: enhanced effectiveness of chromosome identification. 3 ex
