caa a22 4500 388058986 CHVBK 20180307125115.0 cr unu---uuuuu 161130e19980201xx s 000 0 eng 10.1375/twin.1.1.3 doi S1369052300000179 pii (NATIONALLICENCE)cambridge-10.1375/twin.1.1.3 Models for the longitudinal genetic analysis of same-age twins: application to HDL cholesterol [Elektronische Daten] Models are presented for the analysis of longitudinal data from same-age twins which permit the exploration of a remarkably diverse array of alternative explanations for continuity and change during development. Data of this type permit the detection of new sources of genetic or environmental covariation during development that are not expressed at earlier ages and, because they include the effects of age-specific genes, the resulting heritability estimates are more reliable than those obtained from relatives who differ in age. The proposed models were applied to measurements of HDL cholesterol obtained on 81 pairs of monozygotic (MZ) twins and 69 dizygotic (DZ) pairs at 11, 12.5 and 14 years of age. All three MZ co-twin correlations were substantially higher than the self correlations across occasions, suggesting that new sources of genetic or environmental covariation must be expressed during early adolescence. This interpretation was confirmed by analysis of the full covariance matrices which showed that only models which assumed the expression of new or age-specific genes could explain the observed pattern of covariation. Because they include the effects of age-specific genes, the resulting heritabilities (0.80-0.83) were substantially higher than many previous estimates. Copyright © Cambridge University Press 1998 twins nationallicence HDL nationallicence cholesterol nationallicence multivariate nationallicence development nationallicence Nance WE E-mail: nance@hsc.vcu.edu Bodurtha J. Department of Human Genetics. Eaves LJ Department of Human Genetics. Hewitt J. Institute of Behavioral Genetics, University of Colorado, Boulder, Colorado. Maes H. Department of Human Genetics. Segrest J. Department of Medicine, University of Alabama Medical School, Birmingham, Alabama. Meyer J. Millenium Pharmaceuticals Inc., Cambridge, Massachusetts, USA. Neale M. Department of Human Genetics. Schieken R. Department of Pediatrics, Medical College of Virginia of Virginia Commonwealth University, Richmond, Virginia. Twin Research Cambridge University Press 1/1(1998-02-01), 3-8 1369-0523 1:1<3 1998 1 THG https://doi.org/10.1375/twin.1.1.3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1375/twin.1.1.3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Nance WE E-mail: nance@hsc.vcu.edu NATIONALLICENCE 700 1- Bodurtha J. Department of Human Genetics NATIONALLICENCE 700 1- Eaves LJ Department of Human Genetics NATIONALLICENCE 700 1- Hewitt J. Institute of Behavioral Genetics, University of Colorado, Boulder, Colorado NATIONALLICENCE 700 1- Maes H. Department of Human Genetics NATIONALLICENCE 700 1- Segrest J. Department of Medicine, University of Alabama Medical School, Birmingham, Alabama NATIONALLICENCE 700 1- Meyer J. Millenium Pharmaceuticals Inc., Cambridge, Massachusetts, USA NATIONALLICENCE 700 1- Neale M. Department of Human Genetics NATIONALLICENCE 700 1- Schieken R. Department of Pediatrics, Medical College of Virginia of Virginia Commonwealth University, Richmond, Virginia NATIONALLICENCE 773 0- Twin Research Cambridge University Press 1/1(1998-02-01), 3-8 1369-0523 1:1<3 1998 1 THG CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge