China: A country spanning from central Asia to the Pacific Ocean.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Rural Population: The inhabitants of rural areas or of small towns classified as rural.Geography: The science dealing with the earth and its life, especially the description of land, sea, and air and the distribution of plant and animal life, including humanity and human industries with reference to the mutual relations of these elements. (From Webster, 3d ed)Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Economic Development: Mobilization of human, financial, capital, physical and or natural resources to generate goods and services.Tibet: An autonomous region located in central Asia, within China.Schistosomiasis japonica: Schistosomiasis caused by Schistosoma japonicum. It is endemic in the Far East and affects the bowel, liver, and spleen.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Schistosoma japonicum: A species of trematode blood flukes belonging to the family Schistosomatidae whose distribution is confined to areas of the Far East. The intermediate host is a snail. It occurs in man and other mammals.Cluster Analysis: A set of statistical methods used to group variables or observations into strongly inter-related subgroups. In epidemiology, it may be used to analyze a closely grouped series of events or cases of disease or other health-related phenomenon with well-defined distribution patterns in relation to time or place or both.