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The original version of this Article contained errors in the units of concentration of three reagents listed in the Methods. These errors have all been corrected in both the PDF and HTML versions of the Article.

Compartmentalized self replication (CSR) is widely used for in vitro evolution of thermostable DNA polymerases able to perform PCR in emulsion. We have modified and adapted CSR technique for isothermal DNA amplification using mezophilic phi29 DNA polymerase and whole genome amplification (WGA) reaction. In standard CSR emulsified bacterial cells are disrupted during denaturation step (94-96°C) in the first circles of PCR. Released plasmid DNA that encodes target polymerase and the thermophilic enzyme complement the emulsified PCR reaction mixture and start polymerase gene amplification. To be able to select for mezophilic enzymes we have employed multiple freezing-thawing cycles of emulsion as a bacterial cell wall disruption step instead of high temperature incubation. Subsequently WGA like plasmid DNA amplification could be performed by phi29 DNA polymerase applying different selection pressure conditions (temperature, buffer composition, modified dNTP, time, etc.). In our case the library of random phi29 DNA polymerase mutants was subjected to seven selection rounds of isothermal CSR (iCSR). After the selection polymerase variant containing the most frequent mutations was constructed and characterized. The mutant phi29 DNA polymerase can perform WGA at elevated temperatures (40-42°C), generate two to five times more of DNA amplification products, and has significantly increased half-life at 30 and 40°C, both in the presence or the absence of DNA substrate.

Genetic Variability Associated with Angiotensin Converting Enzyme (ACE) Gene Polymorphism in Sportsmen Pursuing Different Sports The purpose of the study was to determine angiotensin converting enzyme (ACE) gene polymorphisms in sportsmen and sedentary individuals and to evaluate the differences in frequencies of ACE genotype and allele distribution among sportsmen who are involved in different sports. In this study 255 participants were analysed: 116 sedentary individuals and 139 sportsmen. Sportsmen were differentiated into separate groups according to various sports: endurance, strength requiring, cyclic and acyclic sports. DNA was purified from peripheral blood with a DNA purification kit "Fermentas". ACE gene polymorphic region was amplified by polymerase chain reaction (PCR). DNA electrophoresis was used to separate DNA fragments by size. Bands were visualised under ultra violet (UV) light. The frequency of D allele was higher than I allele in sedentary individuals; the sportsmen had higher frequency of I allele. The X2 test showed allele selection in sedentary individuals. Frequency of the I allele among the individuals who belong to endurance requiring sports was higher than was the D allele, while among the individuals who belong to sports requiring strength, the D and I allele frequences were equal. Differences in the individuals who belong to acyclic sports group were not significant — the frequency of I allele was much higher than D in the cyclic sports group. D allele frequency was twice higher than I allele among wrestlers.