Prehypertension in the Era of Personalized Medicine in 2017

Genome-wide association studies or GWAS yielded an impressive amount of data that improved the understanding of complex diseases. However, the initial results were deceiving, when the early GWAS of Wellcome Trust, that was successful in reporting many significant associations for several diseases, claimed that no association could be observed for hypertension. It is only later, using carefully collected phenotypes on over 120,000 subjects that 29 SNPs were found to be significantly associated with hypertension. To explain a meaningful proportion of variability in a complex trait and, more importantly, to use this knowledge in risk assessment at an individual level, one needs to construct a genetic (polygenic) risk score (GRS) based on a large number of genotyped variants. From initial 5 to 10 allele-containing GRS reports, more recent publications combine hundreds or even thousands of alleles into so-called polyGRS (or PRS). As the number of SNPs included in the GRS increases, the accuracy of PolyGRS-based risk estimate improves. Any PolyGRS that is predictive in the long term (from birth on) and that has a predictive performance as good as “traditional risk factors,” would significantly improve the clinical utility of existing risk assessment algorithms for hypertension, encouraging its implementation in the practice of personalized medicine.