Four different strategies were used. First, a prospective, epidemiologic survey of 24,000 pregnancies was conducted to determine the role of the T235 variant in common disorders of pregnancy. From this population, nulligravida volunteers, 150 who were homozygous for T235 variant and 150 who were homozygous for the alternative M235 allele, were selected for a longitudinal study of maternal-fetal physiology and biochemistry in order to determine how and when the T235 variant exerted its adverse effect. Taking advantage of the large average family size in Utah, the female relatives of women with preeclampsia were also studied in order to define the genetics of important angiotensinogen variants. Finally, DNA from preeclamptic patients was examined for additional mutations in the angiotensinogen gene which may offer unique pathophysiologic insight.