Basal high blood pressure (BP) in the male and female F2 progeny produced by crosses between Wistar Kyoto rats (WKY/lzm) and stroke-prone spontaneously hypertensive rats (SHRSP/lzm) linked strongly with the leukosialin locus on chromosome 1. 2. Excess salt intake caused elevation of BP and the response was larger in the females than the males. 3. In the male F2 progeny, salt-sensitive hypertension significantly cosegregated with the RR1023 marker on chromosome 10, rather than with the angiotensin converting enzyme locus. 4. In the female F2 progeny, salt-sensitive hypertension significantly linked with the MitR244 marker on chromosome 3.