a Background: Blood pressure (BP) is known to aggregate in families. Yet, heritability estimates are populationspecific and no Swiss data have been published so far. We estimated the heritability of ambulatory and office BP in a Swiss population-based sample.
Methods: The Swiss Kidney Project on Genes inHypertension is a population-based family study focusing on BP genetics. Office and ambulatory BP were measured in 1009 individuals from 271 nuclear families. Heritability was estimated for SBP, DBP, and pulse pressure using a maximum likelihood method implanted in the Statistical Analysis in Genetic Epidemiology software.
Results:The 518 women and 491 men included in this analysis had a mean (AESD) age of 48.3 (AE17.4) and 47.3 (AE17.7) years, and a mean BMI of 23.8 (AE4.2) and 25.9 (AE4.1) kg/m 2 , respectively. Narrow-sense heritability estimates (AEstandard error) for ambulatory SBP, DBP, and pulse pressure were 0.37 AE 0.07, 0.26 AE 0.07, and 0.29 AE 0.07 for 24-h BP; 0.39 AE 0.07, 0.28 AE 0.07, and 0.27 AE 0.07 for day BP; and 0.25 AE 0.07, 0.20 AE 0.07, and 0.30 AE 0.07 for night BP, respectively (all P < 0.001). Heritability estimates for office SBP, DBP, and pulse pressure were 0.21 AE 0.08, 0.25 AE 0.08, and 0.18 AE 0.07 (all P < 0.01).
Conclusions:We found significant heritability estimates for both ambulatory and office BP in this Swiss populationbased study. Our findings justify the ongoing search for the genetic determinants of BP.