Related Experiment Video
Updated: Jun 21, 2026

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World
Published on: April 7, 2020
Genetic influences on daytime and night-time blood pressure: similarities and differences
Xiaoling Wang1, Xiuhua Ding, Shaoyong Su
1Department of Pediatrics, Medical College of Georgia, Georgia Prevention Institute, Augusta, GA 30912, USA. xwang@mcg.edu
Objective:
To examine whether the genetic influences on blood pressure (BP) during night-time are different from those during daytime and the extent to which they depend on ethnicity or sex.
Methods:
Ambulatory BP was measured in 240 European-American and 190 African-American twins (mean +/- SD age, 17.2 +/- 3.4). Individuals with night-time BP falls more than 10% of the daytime values were defined as dippers. A bivariate analysis of the daytime and the night-time BP levels, as well as a liability-threshold model of dippers vs. nondippers were used.
Results:
Bivariate model fitting showed no ethnic or sex differences for any of the measures, with heritabilities of 0.70 and 0.68 for SBP and 0.70 and 0.64 for DBP at daytime and at night-time. The genetic influences on daytime and night-time were not significantly different for SBP or DBP. The bivariate analysis also indicated that about 56 and 33% of the heritabilities of night-time SBP and DBP could be attributed to genes that also influenced daytime levels. The specific heritabilities due to genetic effects only influencing night-time values were 0.30 for SBP and 0.43 for DBP. The heritabilities of systolic and diastolic dipping were 0.59 and 0.81, respectively.
Conclusion:
Independent of ethnicity and sex, an overlap exists between genes that influence daytime and night-time BP, as well as a significant genetic component that is specific to the night-time BP. These findings suggest that different genes or sets of genes contribute to BP regulation at daytime and night-time.
Related Concept Videos
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Factors affecting Blood pressure
Physiological Factors:
Circadian Rhythms and Gene Regulation
Circadian Rhythms and Gene Regulation
Neural Regulation of Blood Pressure
Baroreceptor Reflex
Baroreceptors, located in the carotid sinuses and aortic arch, detect changes in blood pressure. When blood pressure rises, these stretch-sensitive receptors...
Hypertension and Regulation of Blood Pressure

