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A comparative analysis of the total cellular DNA in certain parthenogenetic specimens of the silkworm (Bombyx mori), produced from the females of the parthenogenetic strains by two types of parthenogenesis, has been performed through the application of the DNA fingerprinting method based on M13 phage DNA as a hybridization probe. It has been shown that parental specimens and their genetically identical off-springs produced through ameiotic parthenogenesis have identical patterns of hybridization with the hypervariable DNA fragments. The off-springs produced through the meiotic type of parthenogenesis have individual-specific patterns of hybridization, revealing a high level of polymorphism of individual genotypes. The results obtained testify to the effectiveness and reliability of this promising method for identification of genotypic variability, marking and genomic characterization of parthenogenetic clones in the silkworm.

Hypervariable polymorphic patterns were detected with M13 phage DNA as a probe in genomic DNA of organisms belonging to different taxonomic groups including animals (vertebrates and invertebrates), plants and microorganisms. Individual-specific restriction pattern analysis (DNA fingerprinting) with this probe proved to be useful for individual identification, analysis of somatic stability and paternity testing in man. The nuclear type of inheritance indicates that the hypervariable DNA regions in question are located in the chromosomes, not in the mitochondrial DNA. The data obtained also demonstrate a potential range of M13 DNA applications as a probe for DNA fingerprinting of animals, plants and microorganisms, particularly for the determination of inbred lines, identification of bacterial strains and establishing stock, variety and strain distinctions.

Two clones have been selected from a human fibroblast cDNA bank. By DNA sequencing the clones were shown to contain Alu elements located near the ends of the cDNA inserts. DNA of the clones was used for Northern blot hybridization analysis of a number of poly(A)-containing RNAs from normal human tissues (brain, stomach, uterus, spleen, fibroblasts) and tumors (neurinoma, glioma, neuroblastoma, liposarcoma, adrenal cortex adenocarcinoma). All RNA samples reveal a heterodisperse distribution of Alu transcripts with discrete bands in the region of 7-12 S RNA. The majority of these small poly(A)+ Alu+ RNAs contain Alu sequences only in one (canonical) orientation with functional signals including the split promoter for RNA polymerase III.

The cytoplasmic poly(A)+RNAs containing ubiquitous B1 and B2 repeats of the mouse genome in normal tissues and tumors have been studied. Only one strand of the repeats is represented in cytoplasmic RNA in all the cases. Some tumor cells were found to be enriched in 1.4 kb B1+mRNA, 1.6 kb B2+mRNA and small (0.2-04 kb) B1+ and B2+ poly(A)+RNAs. On the other hand, mouse liver and kidney contained high amounts of 2 kb B2+mRNA. Its content increased noticeably in the regenerating liver, but in hepatoma it dropped to a zero level. Thus, the switching on (or off) of B1- and B2-containing mRNAs occurred noncoordinately. At the same time, the activation of the synthesis of small B2+RNA and small B1+RNA was simultaneous.