Estimating heritability of height without zygosity information for twins under five years in low- and middle-income countries: An application of normal finite mixture distribution models. (March 2022)

• Record Type: Journal Article
• Authors: Karlsson, Omar; Domingue, Benjamin W.; Kim, Rockli; Subramanian, S.V.
• Is Part Of: SSM - population health. Volume 17(2022)
• Publication Date: 2022-03
• Subjects: Heritability -- Twin studies -- Height -- Unknown zygosity -- Low- and middle-income countries; Social medicine -- Periodicals; Medical anthropology -- Periodicals; Public health -- Periodicals; Psychology -- Periodicals; Medicine -- Periodicals; 362.105
• DOI: 10.1016/j.ssmph.2022.101043
• Languages: English
• ISSNs: 2352-8273

Abstract

Abstract: Twin studies are widely used to estimate heritability of traits and typically rely on knowing the zygosity of twin pairs in order to determine variation attributable to genetics. Most twin studies are conducted in high resource settings. Large scale household survey data, such as the Demographic and Health Surveys, collect various biomarkers for children under five years old in low- and middle-income countries. These data include twins but no information on zygosity. We applied mixture models to obtain heritability estimates without knowing zygosity of twins, using 249 Demographic and Health Surveys from 79 low- and middle-income countries (14, 524 twin pairs). We focused on height of children, adjusted for age and sex, but also provided estimates for other biomarkers available in the data. We estimated that the heritability of height in our sample was 46%. Highlights: Mixture model was used to obtain heritability estimates for biomarkers for children under five without zygosity information. 46% of height was determined by heritability. Heritability estimate was 0.54 for weight-for-age z-score and 0.51 for residualized weight. An implausible heritability estimate of 0.93 was found for weight-for-height z-score. Birthweight had a heritability estimate of 0.71 and hemoglobin level had a heritability estimate of 0.61.