Assessment of cardiovascular disease risk factors in a genetically homogenous population of Parsi Zoroastrians in the United States: A pilot study

Objective Genetically isolated and homogenous populations are ideal for detecting genes underlying common complex diseases. The use of isolated populations with reduced disease heterogeneity has led to significant gene discoveries in the past. The aim of this pilot study was to assess the prevalence of cardiovascular disease (CVD) risk phenotypes in a genetically homogenous population of Parsi Zoroastrians in the United States. Methods Anthropometrics, blood pressure, and medical history were collected from 152 men and 186 women participating in a pilot study as part of the Parsi Family Study. The relative pairs used in the study included 60 parent–off springs, 28 siblings, 6 grandparent–grandchild, 7 avuncular, 18 half-siblings, 7 half-avuncular, and one half-first cousin. Estimates of genetic and environmental influence were calculated using a maximum likelihood-based variance components method implemented in SOLAR. Results The prevalence of overweight/obesity in adults (62%) was on par with current US prevalence. Hypertension and prehypertension were prevalent in 16% and 46% of the participants, respectively. The quantitative genetic analysis revealed significant heritabilities for all anthropometric phenotypes (P \u3c 0.05). Significant phenotypic correlations were found between blood pressure and anthropometric phenotypes (P \u3c 0.001), whereas significant genetic correlation was found for only diastolic blood pressure and fat free mass (rhoG = −0.88, P \u3c 0.05). Conclusion These preliminary data show significant additive genetic effects on CVD-related phenotypes in this population. Our findings represent the first epidemiological data in Parsi Zoroastrians in the United States and offer excellent promise for future genetic studies in this population. Am. J. Hum. Biol. 28:440–443, 2016. © 2016 Wiley Periodicals, Inc