Family environment and the malleability of cognitive ability: A Swedish national home-reared and adopted-away cosibling control study.
(2015) In Proceedings of the National Academy of Sciences 112(15). p.4612-4617- Abstract
- Cognitive ability strongly aggregates in families, and prior twin and adoption studies have suggested that this is the result of both genetic and environmental factors. In this study, we used a powerful design-home-reared and adopted-away cosibling controls-to investigate the role of the rearing environment in cognitive ability. We identified, from a complete national Swedish sample of male-male siblings, 436 full-sibships in which at least one member was reared by one or more biological parents and the other by adoptive parents. IQ was measured at age 18-20 as part of the Swedish military service conscription examination. Parental educational level was rated on a 5-point scale. Controlling for clustering of offspring within biological... (More)
- Cognitive ability strongly aggregates in families, and prior twin and adoption studies have suggested that this is the result of both genetic and environmental factors. In this study, we used a powerful design-home-reared and adopted-away cosibling controls-to investigate the role of the rearing environment in cognitive ability. We identified, from a complete national Swedish sample of male-male siblings, 436 full-sibships in which at least one member was reared by one or more biological parents and the other by adoptive parents. IQ was measured at age 18-20 as part of the Swedish military service conscription examination. Parental educational level was rated on a 5-point scale. Controlling for clustering of offspring within biological families, the adopted siblings had an IQ 4.41 (SE = 0.75) points higher than their nonadopted siblings. Each additional unit of rearing parental education was associated with 1.71 (SE = 0.44) units of IQ. We replicated these results in 2,341 male-male half-sibships, in which, controlling for clustering within families, adoption was associated with a gain of IQ of 3.18 (SE = 0.34) points. Each additional unit of rearing parental education was associated with 1.94 (SE = 0.18) IQ units. Using full- and half-sibling sets matched for genetic background, we found replicated evidence that (i) rearing environment affects IQ measured in late adolescence, and (ii) a portion of the IQ of adopted siblings could be explained by the educational level of their adoptive parents. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/5360312
- author
- Kendler, Ken LU ; Turkheimer, Eric ; Ohlsson, Henrik LU ; Sundquist, Jan LU and Sundquist, Kristina LU
- organization
- publishing date
- 2015
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Proceedings of the National Academy of Sciences
- volume
- 112
- issue
- 15
- pages
- 4612 - 4617
- publisher
- National Academy of Sciences
- external identifiers
-
- pmid:25831538
- wos:000352856800042
- scopus:84928152357
- pmid:25831538
- ISSN
- 1091-6490
- DOI
- 10.1073/pnas.1417106112
- language
- English
- LU publication?
- yes
- id
- be8070d3-0743-4a19-b3ff-f6bc49ded93b (old id 5360312)
- alternative location
- http://www.ncbi.nlm.nih.gov/pubmed/25831538?dopt=Abstract
- date added to LUP
- 2016-04-01 10:15:04
- date last changed
- 2022-04-12 03:29:56
@article{be8070d3-0743-4a19-b3ff-f6bc49ded93b,
abstract = {{Cognitive ability strongly aggregates in families, and prior twin and adoption studies have suggested that this is the result of both genetic and environmental factors. In this study, we used a powerful design-home-reared and adopted-away cosibling controls-to investigate the role of the rearing environment in cognitive ability. We identified, from a complete national Swedish sample of male-male siblings, 436 full-sibships in which at least one member was reared by one or more biological parents and the other by adoptive parents. IQ was measured at age 18-20 as part of the Swedish military service conscription examination. Parental educational level was rated on a 5-point scale. Controlling for clustering of offspring within biological families, the adopted siblings had an IQ 4.41 (SE = 0.75) points higher than their nonadopted siblings. Each additional unit of rearing parental education was associated with 1.71 (SE = 0.44) units of IQ. We replicated these results in 2,341 male-male half-sibships, in which, controlling for clustering within families, adoption was associated with a gain of IQ of 3.18 (SE = 0.34) points. Each additional unit of rearing parental education was associated with 1.94 (SE = 0.18) IQ units. Using full- and half-sibling sets matched for genetic background, we found replicated evidence that (i) rearing environment affects IQ measured in late adolescence, and (ii) a portion of the IQ of adopted siblings could be explained by the educational level of their adoptive parents.}},
author = {{Kendler, Ken and Turkheimer, Eric and Ohlsson, Henrik and Sundquist, Jan and Sundquist, Kristina}},
issn = {{1091-6490}},
language = {{eng}},
number = {{15}},
pages = {{4612--4617}},
publisher = {{National Academy of Sciences}},
series = {{Proceedings of the National Academy of Sciences}},
title = {{Family environment and the malleability of cognitive ability: A Swedish national home-reared and adopted-away cosibling control study.}},
url = {{http://dx.doi.org/10.1073/pnas.1417106112}},
doi = {{10.1073/pnas.1417106112}},
volume = {{112}},
year = {{2015}},
}