OBJECTIVETo construct a genetic map based on data from the Chinese population in northern part of China and to compare relationship between physical distance and genetic distance on chromosome 22.

METHODSPCR amplification was employed to genotype 6 STR loci on chromosome 22, and pedigree analysis was performed.

RESULTSA genetic map of Chinese Han population in the northern part of China was constructed and a preliminary comparison of the physical and genetic distances between 6 STR loci on chromosome 22 was made.

CONCLUSIONThere is complex relationship between genetic distance and physical distance: the distance between STR loci is related to physical distance but also recombination fraction, and there are differences of the genetic and physical distances on chromosome 22 between Chinese and Caucasian, and between the male and female.