Amy H. T. Davis

Direct sequencing is more accurate and feasible in detecting single nucleotide polymorphisms than RFLP: using human vascular endothelial growth factor gene as a model.

Since the sequencing of the human genome, there has been increased interest in understanding the distribution and effects of genetic variations among individuals. Restriction fragment length polymorphism (RFLP) is a well-established and frequently used method for genotyping. This method, however, is indirect and has a number of limitations. It is thus important to reevaluate the use of RFLP in light of more contemporary methods of genotyping. The specific aims of this study are to (a) compare genotyping methods of traditional RFLP with contemporary direct sequencing for accurate identification of polymorphisms within the human vascular endothelial growth factor (VEGF) gene and (b) describe distribution of a known single nucleotide polymorphism (SNP) in the VEGF gene in a sample composed of 50 healthy volunteers. Polymerase chain reaction (PCR) was used to amplify the initial sample of DNA. Genotypes of a G-to-A substitution (GG, AG, AA) at -1154 were analyzed by RFLP and direct sequencing. RFLP was unable to discriminate among the three possible genotypes, whereas direct sequencing clearly identified genotype for all 50 samples. Observed genotype frequencies were comparable with the Hardy-Weinberg principle. This comparative study provides justification for selecting direct sequencing instead of RFLP for detecting SNPs in selected genes.

Health-Related Quality of Life by the Type of Physical Activity in Korea

This study examined if health-related quality of life is different based upon the type of physical activity performed by 1,266 community-dwelling adults in urban area of Korea. Physical activity was categorized into (a) work, (b) leisure (non-sport), and (c) sports activity. The results indicated that only leisure and sports activity were positively correlated with health-related quality of life. Therefore, it is recommended that leisure and sports activity must be encouraged, especially to people who do not think that they need any leisure or sports activity because they are very active physically at work.