Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk.
Because of the ubiquitous adaptability of our material culture, some human populations have occupied extreme environments that intensified selection on existing genomic variation. By 32,000 years ago, people were living in Arctic Beringia, and during the Last Glacial Maximum (LGM; 28,000-18,000 y ag...
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ftcdlib:oai:escholarship.org/ark:/13030/qt5sj744qv 2023-05-15T15:14:25+02:00 Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. Hlusko, Leslea J Carlson, Joshua P Chaplin, George Elias, Scott A Hoffecker, John F Huffman, Michaela Jablonski, Nina G Monson, Tesla A O'Rourke, Dennis H Pilloud, Marin A Scott, G Richard E4426 - E4432 2018-05-01 application/pdf https://escholarship.org/uc/item/5sj744qv unknown eScholarship, University of California qt5sj744qv https://escholarship.org/uc/item/5sj744qv public Proceedings of the National Academy of Sciences of the United States of America, vol 115, iss 19 Mammary Glands Human Milk Humans Fatty Acids Vitamin D Cold Climate Pregnancy Maternal-Fetal Exchange Alleles Female Male Edar Receptor Selection Genetic Beringia UV radiation adaptation dental anthropology mammary epithelium article 2018 ftcdlib 2021-07-05T17:07:40Z Because of the ubiquitous adaptability of our material culture, some human populations have occupied extreme environments that intensified selection on existing genomic variation. By 32,000 years ago, people were living in Arctic Beringia, and during the Last Glacial Maximum (LGM; 28,000-18,000 y ago), they likely persisted in the Beringian refugium. Such high latitudes provide only very low levels of UV radiation, and can thereby lead to dangerously low levels of biosynthesized vitamin D. The physiological effects of vitamin D deficiency range from reduced dietary absorption of calcium to a compromised immune system and modified adipose tissue function. The ectodysplasin A receptor (EDAR) gene has a range of pleiotropic effects, including sweat gland density, incisor shoveling, and mammary gland ductal branching. The frequency of the human-specific EDAR V370A allele appears to be uniquely elevated in North and East Asian and New World populations due to a bout of positive selection likely to have occurred circa 20,000 y ago. The dental pleiotropic effects of this allele suggest an even higher occurrence among indigenous people in the Western Hemisphere before European colonization. We hypothesize that selection on EDAR V370A occurred in the Beringian refugium because it increases mammary ductal branching, and thereby may amplify the transfer of critical nutrients in vitamin D-deficient conditions to infants via mothers' milk. This hypothesized selective context for EDAR V370A was likely intertwined with selection on the fatty acid desaturase (FADS) gene cluster because it is known to modulate lipid profiles transmitted to milk from a vitamin D-rich diet high in omega-3 fatty acids. Article in Journal/Newspaper Arctic Beringia University of California: eScholarship Arctic |
institution |
Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
unknown |
topic |
Mammary Glands Human Milk Humans Fatty Acids Vitamin D Cold Climate Pregnancy Maternal-Fetal Exchange Alleles Female Male Edar Receptor Selection Genetic Beringia UV radiation adaptation dental anthropology mammary epithelium |
spellingShingle |
Mammary Glands Human Milk Humans Fatty Acids Vitamin D Cold Climate Pregnancy Maternal-Fetal Exchange Alleles Female Male Edar Receptor Selection Genetic Beringia UV radiation adaptation dental anthropology mammary epithelium Hlusko, Leslea J Carlson, Joshua P Chaplin, George Elias, Scott A Hoffecker, John F Huffman, Michaela Jablonski, Nina G Monson, Tesla A O'Rourke, Dennis H Pilloud, Marin A Scott, G Richard Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. |
topic_facet |
Mammary Glands Human Milk Humans Fatty Acids Vitamin D Cold Climate Pregnancy Maternal-Fetal Exchange Alleles Female Male Edar Receptor Selection Genetic Beringia UV radiation adaptation dental anthropology mammary epithelium |
description |
Because of the ubiquitous adaptability of our material culture, some human populations have occupied extreme environments that intensified selection on existing genomic variation. By 32,000 years ago, people were living in Arctic Beringia, and during the Last Glacial Maximum (LGM; 28,000-18,000 y ago), they likely persisted in the Beringian refugium. Such high latitudes provide only very low levels of UV radiation, and can thereby lead to dangerously low levels of biosynthesized vitamin D. The physiological effects of vitamin D deficiency range from reduced dietary absorption of calcium to a compromised immune system and modified adipose tissue function. The ectodysplasin A receptor (EDAR) gene has a range of pleiotropic effects, including sweat gland density, incisor shoveling, and mammary gland ductal branching. The frequency of the human-specific EDAR V370A allele appears to be uniquely elevated in North and East Asian and New World populations due to a bout of positive selection likely to have occurred circa 20,000 y ago. The dental pleiotropic effects of this allele suggest an even higher occurrence among indigenous people in the Western Hemisphere before European colonization. We hypothesize that selection on EDAR V370A occurred in the Beringian refugium because it increases mammary ductal branching, and thereby may amplify the transfer of critical nutrients in vitamin D-deficient conditions to infants via mothers' milk. This hypothesized selective context for EDAR V370A was likely intertwined with selection on the fatty acid desaturase (FADS) gene cluster because it is known to modulate lipid profiles transmitted to milk from a vitamin D-rich diet high in omega-3 fatty acids. |
format |
Article in Journal/Newspaper |
author |
Hlusko, Leslea J Carlson, Joshua P Chaplin, George Elias, Scott A Hoffecker, John F Huffman, Michaela Jablonski, Nina G Monson, Tesla A O'Rourke, Dennis H Pilloud, Marin A Scott, G Richard |
author_facet |
Hlusko, Leslea J Carlson, Joshua P Chaplin, George Elias, Scott A Hoffecker, John F Huffman, Michaela Jablonski, Nina G Monson, Tesla A O'Rourke, Dennis H Pilloud, Marin A Scott, G Richard |
author_sort |
Hlusko, Leslea J |
title |
Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. |
title_short |
Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. |
title_full |
Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. |
title_fullStr |
Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. |
title_full_unstemmed |
Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. |
title_sort |
environmental selection during the last ice age on the mother-to-infant transmission of vitamin d and fatty acids through breast milk. |
publisher |
eScholarship, University of California |
publishDate |
2018 |
url |
https://escholarship.org/uc/item/5sj744qv |
op_coverage |
E4426 - E4432 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Beringia |
genre_facet |
Arctic Beringia |
op_source |
Proceedings of the National Academy of Sciences of the United States of America, vol 115, iss 19 |
op_relation |
qt5sj744qv https://escholarship.org/uc/item/5sj744qv |
op_rights |
public |
_version_ |
1766344873785425920 |