[Detection of single base polymorphism in p53 gene by ligase detection reaction and rolling circle amplification on microarrays].

We combined three modern technologies of single base polymorphism detection in human genome: ligase detection reaction, rolling circle amplification and IMAGE hydro-gel microarrays. Polymorphism in target DNA was tested by selective ligation on microarray. Product of the ligase reaction was determined in microarray gel pads by rolling circle amplification. Two different methods were compared. In first, selective ligation of short oligonucleotides immobilized on microarray was used with subsequent amplification on preformed circle probe ("common circle"). The circle probe was designed especially for human genome research. In second variant, allele-specific padlock probes that may be circularized by selective ligation were immobilized on microarray. Polymorphism of codon 72 in human p53 gene was used as a biological model. It was shown that LDR/RCA on microarray is a quantitative reaction and gives high discrimination of alleles. Principles and perspectives of selective ligation and rolling circle amplification are being discussed.

[Analysis of chromosome translocations involving MML by hybridization with an oligonucleotide microarray]. / Analiz khromosomnykh translokatsii s uchastiem gena MLL metodom gibridizatsii s oligonukleotidnym mikrochipami.

Identification of chromosome rearrangements is of importance for exact diagnosis, risk assessment, and therapy in blood malignancies. A new method was proposed for rapid and accurate identification of leukemia forms caused by chromosome rearrangements involving MLL (11q23). The method combines reverse transcription-multiplex PCR and hybridization with an oligonucleotide microarray. The microarray was designed to detect the five most common MLL rearrangements: t(4;11) MLL/AF4, t(9;11) MLL/AF9, t(11;19) MLL/ELL, t(11;19) MLL/ENL, and dup(11) MLL/MLL. With clinical specimens, the method was shown to efficiently identify the chromosome translocations in leukemia patients.

[Comparison of the isoacceptor makeup of transfer RNA for 2 early stages in the development of loach embryos]. / Sopostavlenie izoaktseptornogo sostava transportnykh RNK dlia dvukh rannikh stadi56I RAZVITIIIA ZARODYSHEI V'IUNA.

The chromatographic profiles of isoacceptor tRNA's for 9 amino acids from the loach embryos at two early developmental stages were compared by the method of chromatography on sepharose column in the decreasing gradient of ammonium sulphate concentration to elucidate the possible role of tRNA in the control of early embryogenesis processes. Certain differences both in the proportions of some isoacceptor peaks and their relative positions on the chromatographic profile were found for 8 aminoacyl tRNA. Methionyl-tRNA was represented by one constant peak.