{"id":11369,"date":"2022-06-12T09:12:49","date_gmt":"2022-06-12T09:12:49","guid":{"rendered":"https:\/\/www.rhesusnegative.net\/staynegative\/?p=11369"},"modified":"2022-01-18T10:33:38","modified_gmt":"2022-01-18T10:33:38","slug":"handedness-nature-or-nurture","status":"publish","type":"post","link":"https:\/\/www.rhesusnegative.net\/staynegative\/handedness-nature-or-nurture\/","title":{"rendered":"Handedness: Nature or Nurture?"},"content":{"rendered":"<div style=\"padding-bottom:20px; padding-top:10px;\" class=\"hupso-share-buttons\"><!-- Hupso Share Buttons - https:\/\/www.hupso.com\/share\/ --><a class=\"hupso_toolbar\" href=\"https:\/\/www.hupso.com\/share\/\"><img data-recalc-dims=\"1\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/static.hupso.com\/share\/buttons\/share-medium.png?w=640&#038;ssl=1\" style=\"border:0px; padding-top:5px; float:left;\" alt=\"Share Button\"\/><\/a><script type=\"text\/javascript\">var hupso_services_t=new Array(\"Twitter\",\"Facebook\",\"Pinterest\",\"Linkedin\");var hupso_background_t=\"#EAF4FF\";var hupso_border_t=\"#66CCFF\";var hupso_toolbar_size_t=\"medium\";var hupso_twitter_via = \"datebytype\";var hupso_image_folder_url = \"\";var hupso_twitter_via=\"datebytype\";var hupso_url_t=\"\";var hupso_title_t=\"Handedness: Nature or Nurture?\";<\/script><script type=\"text\/javascript\" src=\"https:\/\/static.hupso.com\/share\/js\/share_toolbar.js\"><\/script><!-- Hupso Share Buttons --><\/div>\n<figure class=\"wp-block-embed-youtube aligncenter wp-block-embed is-type-video is-provider-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Why are so many Rh negatives left-handed?\" width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/Km8cB3H67ZE?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<p>Handedness displays a complex inheritance pattern. For example, if both parents of a child are left-handed, there is a 26% chance of that child being left-handed.&nbsp;A large study of twins from 25,732 families by Medland et al. (2006) indicates that the&nbsp;heritability&nbsp;of handedness is roughly 24%.<\/p>\n\n\n\n<figure class=\"wp-block-embed-wordpress wp-block-embed is-type-wp-embed is-provider-rh-negative-blood-and-people\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"149gbGFS3a\"><a href=\"https:\/\/www.rhesusnegative.net\/staynegative\/why-are-so-many-rh-negatives-left-handed\/\">Why are so many Rh negatives left-handed?<\/a><\/blockquote><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; clip: rect(1px, 1px, 1px, 1px);\" title=\"&#8220;Why are so many Rh negatives left-handed?&#8221; &#8212; The Rh Negative Blog\" src=\"https:\/\/www.rhesusnegative.net\/staynegative\/why-are-so-many-rh-negatives-left-handed\/embed\/#?secret=fav2WD2Gcc#?secret=149gbGFS3a\" data-secret=\"149gbGFS3a\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p> In addition, parent and self-reported handedness was available for 60 pairs of twins who had participated in both the Brisbane adolescent study and Australian Twin ADHD Project. The polychoric correlation between parent and self-reported handedness of .970 indicates the high reliability of parental report in these data (which may be expected as twins are allowed to help the parents complete the questionnaires). These results suggest that parental report is a valid method of data collection and comparable with self-report in terms of accuracy when the measures of handedness are salient. Based on these results it was decided that parental reports collected in the Australian Twin ADHD Project and younger Netherlands twin studies could be used to assess the handedness of their offspring.<br><br> <\/p><cite>https:\/\/www.ncbi.nlm.nih.gov\/pmc\/articles\/PMC2755095\/<\/cite><\/blockquote>\n\n\n\n<p>Two theoretical single-gene models have been proposed to explain the patterns of inheritance of handedness, by Marian Annett&nbsp;of the&nbsp;University of Leicester, and by Chris McManus&nbsp;of&nbsp;UCL.<\/p>\n\n\n\n<p>However, growing evidence from&nbsp;linkage&nbsp;and&nbsp;genome-wide association&nbsp;studies suggests that genetic variance in handedness cannot be explained by a single genetic&nbsp;locus.&nbsp;From these studies, McManus et al. now conclude that handedness is&nbsp;polygenic&nbsp;and estimate that at least 40&nbsp;loci&nbsp;contribute to the trait.<\/p>\n\n\n\n<p>Brandler et al. performed a&nbsp;genome-wide association study&nbsp;for a measure of relative hand skill and found that genes involved in the determination of left\/right asymmetry in the body play a key role in handedness.&nbsp;Brandler and&nbsp;Paracchini&nbsp;suggest the same mechanisms that determine left\/right asymmetry in the body (e.g.&nbsp;nodal signaling&nbsp;and&nbsp;ciliogenesis) also play a role in the development of brain asymmetry (handedness being a reflection of brain asymmetry for motor function).<\/p>\n\n\n\n<p>In 2019, Wiberg et al. performed a genome-wide association study and found that handedness was significantly associated with four loci, three of them in genes encoding proteins involved in brain development.<\/p>\n<div style=\"padding-bottom:20px; padding-top:10px;\" class=\"hupso-share-buttons\"><!-- Hupso Share Buttons - https:\/\/www.hupso.com\/share\/ --><a class=\"hupso_toolbar\" href=\"https:\/\/www.hupso.com\/share\/\"><img data-recalc-dims=\"1\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/static.hupso.com\/share\/buttons\/share-medium.png?w=640&#038;ssl=1\" style=\"border:0px; padding-top:5px; float:left;\" alt=\"Share Button\"\/><\/a><script type=\"text\/javascript\">var hupso_services_t=new Array(\"Twitter\",\"Facebook\",\"Pinterest\",\"Linkedin\");var hupso_background_t=\"#EAF4FF\";var hupso_border_t=\"#66CCFF\";var hupso_toolbar_size_t=\"medium\";var hupso_twitter_via = \"datebytype\";var hupso_image_folder_url = \"\";var hupso_twitter_via=\"datebytype\";var hupso_url_t=\"\";var hupso_title_t=\"Handedness: Nature or Nurture?\";<\/script><script type=\"text\/javascript\" src=\"https:\/\/static.hupso.com\/share\/js\/share_toolbar.js\"><\/script><!-- Hupso Share Buttons --><\/div>","protected":false},"excerpt":{"rendered":"<div style=\"padding-bottom:20px; padding-top:10px;\" class=\"hupso-share-buttons\"><!-- Hupso Share Buttons - https:\/\/www.hupso.com\/share\/ --><a class=\"hupso_toolbar\" href=\"https:\/\/www.hupso.com\/share\/\"><img src=\"https:\/\/static.hupso.com\/share\/buttons\/share-medium.png\" style=\"border:0px; padding-top:5px; float:left;\" alt=\"Share Button\"\/><\/a><script type=\"text\/javascript\">var hupso_services_t=new Array(\"Twitter\",\"Facebook\",\"Pinterest\",\"Linkedin\");var hupso_background_t=\"#EAF4FF\";var hupso_border_t=\"#66CCFF\";var hupso_toolbar_size_t=\"medium\";var hupso_twitter_via = \"datebytype\";var hupso_image_folder_url = \"\";var hupso_twitter_via=\"datebytype\";var hupso_url_t=\"\";var hupso_title_t=\"Handedness: Nature or Nurture?\";<\/script><script type=\"text\/javascript\" src=\"https:\/\/static.hupso.com\/share\/js\/share_toolbar.js\"><\/script><!-- Hupso Share Buttons --><\/div>Handedness displays a complex inheritance pattern. For example, if both parents of a child are left-handed, there is a 26% chance of that child being left-handed.&nbsp;A large study of twins from 25,732 families by Medland et al. (2006) indicates that the&nbsp;heritability&nbsp;of handedness is roughly 24%. In addition, parent and self-reported handedness was available for 60 pairs of twins who had participated in both the Brisbane adolescent study and Australian Twin ADHD Project. The polychoric correlation between parent and self-reported handedness of .970 indicates the high reliability of parental report in these data (which may be expected as twins are allowed to help the parents complete the questionnaires). These results suggest that parental report is a valid method of data collection <div style=\"padding-bottom:20px; padding-top:10px;\" class=\"hupso-share-buttons\"><!-- Hupso Share Buttons - https:\/\/www.hupso.com\/share\/ --><a class=\"hupso_toolbar\" href=\"https:\/\/www.hupso.com\/share\/\"><img src=\"https:\/\/static.hupso.com\/share\/buttons\/share-medium.png\" style=\"border:0px; padding-top:5px; float:left;\" alt=\"Share Button\"\/><\/a><script type=\"text\/javascript\">var hupso_services_t=new Array(\"Twitter\",\"Facebook\",\"Pinterest\",\"Linkedin\");var hupso_background_t=\"#EAF4FF\";var hupso_border_t=\"#66CCFF\";var hupso_toolbar_size_t=\"medium\";var hupso_twitter_via = \"datebytype\";var hupso_image_folder_url = \"\";var hupso_twitter_via=\"datebytype\";var hupso_url_t=\"\";var hupso_title_t=\"Handedness: Nature or Nurture?\";<\/script><script type=\"text\/javascript\" src=\"https:\/\/static.hupso.com\/share\/js\/share_toolbar.js\"><\/script><!-- Hupso Share Buttons --><\/div>","protected":false},"author":1,"featured_media":11382,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"amp_status":"","_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false},"version":2}},"categories":[1],"tags":[],"class_list":["post-11369","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-facts"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.rhesusnegative.net\/staynegative\/wp-content\/uploads\/2022\/01\/maxresdefault.jpg?fit=1280%2C720&ssl=1","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p5DV68-2Xn","_links":{"self":[{"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/posts\/11369","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/comments?post=11369"}],"version-history":[{"count":4,"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/posts\/11369\/revisions"}],"predecessor-version":[{"id":11381,"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/posts\/11369\/revisions\/11381"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/media\/11382"}],"wp:attachment":[{"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/media?parent=11369"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/categories?post=11369"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.rhesusnegative.net\/staynegative\/wp-json\/wp\/v2\/tags?post=11369"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}