484 lines
29 KiB
Text
484 lines
29 KiB
Text
|
||
<!DOCTYPE html>
|
||
<html lang="en" id="understanding_genetics" class="nojs us" data-root="https://medlineplus.gov/">
|
||
|
||
<head>
|
||
|
||
<meta charset="utf-8" />
|
||
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
|
||
<meta http-equiv="window-target" content="_top" />
|
||
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
|
||
<meta name="viewport" content="width=device-width, initial-scale=1" />
|
||
|
||
|
||
|
||
|
||
|
||
<link rel="canonical" href="https://medlineplus.gov/genetics/understanding/traits/handedness/" />
|
||
|
||
|
||
|
||
|
||
<link rel="alternate" hreflang="en" href="https://medlineplus.gov/genetics/understanding/traits/handedness/" />
|
||
<link rel="alternate" hreflang="es" href="https://medlineplus.gov/spanish/genetica/entender/rasgos/destreza/" />
|
||
|
||
|
||
|
||
|
||
<meta name="ac-dictionary" content="medlineplus-ac-dictionary" />
|
||
|
||
<meta name="description" content="Genetic and environmental factors play a role in determining whether you are right handed or left handed. Learn more about how genetics impacts handedness. " />
|
||
|
||
|
||
|
||
<link rel="shortcut icon" href="https://medlineplus.gov/images/favicon.ico" type="image/x-icon" />
|
||
<link rel="apple-touch-icon" href="https://medlineplus.gov/images/touch-icon.png" />
|
||
|
||
|
||
<meta property="fb:app_id" content="1042245625821448" />
|
||
|
||
|
||
|
||
<meta property="og:title" content="Is handedness determined by genetics?: MedlinePlus Genetics" />
|
||
<meta property="og:url" content="https://medlineplus.gov/genetics/understanding/traits/handedness/" />
|
||
|
||
|
||
|
||
<meta property="og:image" content="https://medlineplus.gov/images/GeneticsHumanTraits_Share.jpg" />
|
||
|
||
|
||
|
||
<meta property="og:description" content="Genetic and environmental factors play a role in determining whether you are right handed or left handed. Learn more about how genetics impacts handedness. " />
|
||
|
||
|
||
<meta name="twitter:card" content="summary_large_image" />
|
||
<meta name="twitter:site" content="@medlineplus" />
|
||
<meta name="twitter:creator" content="@medlineplus" />
|
||
<meta name="twitter:title" content="Is handedness determined by genetics?: MedlinePlus Genetics" />
|
||
<meta name="twitter:description" content="Genetic and environmental factors play a role in determining whether you are right handed or left handed. Learn more about how genetics impacts handedness. " />
|
||
<meta name="twitter:image" content="https://medlineplus.gov/images/GeneticsHumanTraits_Share.jpg" />
|
||
|
||
<meta name="twitter:image:alt" content=""/>
|
||
<meta property="og:image:alt" content="" />
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<title>Is handedness determined by genetics?: MedlinePlus Genetics</title>
|
||
|
||
<link rel="stylesheet" href="https://medlineplus.gov/css/common_new.css?1738957191957" />
|
||
<!--[if IE 8]> <link rel="stylesheet" href="https://medlineplus.gov/css/ie8/common.css"> <![endif]-->
|
||
<link rel="stylesheet" href="https://medlineplus.gov/uswds/css/uswds_styles.css" />
|
||
|
||
<link rel="stylesheet" href="https://medlineplus.gov/utilities/lostatic.css">
|
||
|
||
|
||
|
||
<script type="text/javascript">document.getElementsByTagName('html')[0].className = document.getElementsByTagName('html')[0].className.replace( /(?:^|\s)nojs(?!\S)/g , '').trim();</script>
|
||
<script src="https://medlineplus.gov/uswds/js/uswds-init.min.js" type="text/javascript"></script>
|
||
|
||
|
||
|
||
|
||
<script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
|
||
new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
|
||
j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
|
||
'https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
|
||
})(window,document,'script','dataLayer','GTM-MMVM77');</script>
|
||
</head>
|
||
|
||
<body>
|
||
|
||
<noscript><iframe src="https://www.googletagmanager.com/ns.html?id=GTM-MMVM77"
|
||
height="0" width="0" style="display:none;visibility:hidden" title="googletagmanager"></iframe></noscript>
|
||
|
||
|
||
|
||
<a name="top" id="top"></a>
|
||
<a class="hide-offscreen" href="#start">Skip navigation</a>
|
||
|
||
|
||
|
||
<section
|
||
class="usa-banner"
|
||
aria-label="Official website of the United States government"
|
||
>
|
||
<div class="usa-accordion">
|
||
<header class="usa-banner__header">
|
||
<div class="usa-banner__inner">
|
||
<div class="grid-col-auto">
|
||
<img
|
||
aria-hidden="true"
|
||
class="usa-banner__header-flag"
|
||
src="https://medlineplus.gov/uswds/img/us_flag_small.png"
|
||
alt=""
|
||
/>
|
||
</div>
|
||
<div class="grid-col-fill tablet:grid-col-auto" aria-hidden="true">
|
||
<p class="usa-banner__header-text">
|
||
An official website of the United States government
|
||
</p>
|
||
<p class="usa-banner__header-action">Here’s how you know</p>
|
||
</div>
|
||
<button
|
||
type="button"
|
||
class="usa-accordion__button usa-banner__button"
|
||
aria-expanded="false"
|
||
aria-controls="gov-banner-default-default"
|
||
>
|
||
<span class="usa-banner__button-text">Here’s how you know</span>
|
||
</button>
|
||
</div>
|
||
</header>
|
||
<div
|
||
class="usa-banner__content usa-accordion__content"
|
||
id="gov-banner-default-default"
|
||
>
|
||
<div class="grid-row grid-gap-lg">
|
||
<div class="usa-banner__guidance tablet:grid-col-6">
|
||
<img
|
||
class="usa-banner__icon usa-media-block__img"
|
||
src="https://medlineplus.gov/uswds/img/icon-dot-gov.svg"
|
||
role="img"
|
||
alt=""
|
||
aria-hidden="true"
|
||
/>
|
||
<div class="usa-media-block__body">
|
||
<p>
|
||
<strong>Official websites use .gov</strong><br />A
|
||
<strong>.gov</strong> website belongs to an official government
|
||
organization in the United States.
|
||
</p>
|
||
</div>
|
||
</div>
|
||
<div class="usa-banner__guidance tablet:grid-col-6">
|
||
<img
|
||
class="usa-banner__icon usa-media-block__img"
|
||
src="https://medlineplus.gov/uswds/img/icon-https.svg"
|
||
role="img"
|
||
alt=""
|
||
aria-hidden="true"
|
||
/>
|
||
<div class="usa-media-block__body">
|
||
<p>
|
||
<strong>Secure .gov websites use HTTPS</strong><br />A
|
||
<strong>lock</strong> (
|
||
<span class="icon-lock"
|
||
><svg
|
||
xmlns="http://www.w3.org/2000/svg"
|
||
width="52"
|
||
height="64"
|
||
viewBox="0 0 52 64"
|
||
class="usa-banner__lock-image"
|
||
role="img"
|
||
aria-labelledby="banner-lock-description-default"
|
||
focusable="false"
|
||
>
|
||
<title id="banner-lock-title-default">Lock</title>
|
||
<desc id="banner-lock-description-default">Locked padlock icon</desc>
|
||
<path
|
||
fill="#000000"
|
||
fill-rule="evenodd"
|
||
d="M26 0c10.493 0 19 8.507 19 19v9h3a4 4 0 0 1 4 4v28a4 4 0 0 1-4 4H4a4 4 0 0 1-4-4V32a4 4 0 0 1 4-4h3v-9C7 8.507 15.507 0 26 0zm0 8c-5.979 0-10.843 4.77-10.996 10.712L15 19v9h22v-9c0-6.075-4.925-11-11-11z"
|
||
/>
|
||
</svg> </span
|
||
>) or <strong>https://</strong> means you’ve safely connected to
|
||
the .gov website. Share sensitive information only on official,
|
||
secure websites.
|
||
</p>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
</section>
|
||
|
||
|
||
<div id="mplus-wrap">
|
||
<header>
|
||
<div id="mplus-header">
|
||
|
||
<div id="mplus-orgs">
|
||
<a href="https://www.nih.gov/" class="nih-org" target="_blank" title="National Institutes of Health">
|
||
<img class="nihlogo" src="https://medlineplus.gov/images/nihlogo.png" alt="National Institutes of Health"/>
|
||
</a><a href="https://www.nlm.nih.gov/" target="_blank"> National Library of Medicine</a>
|
||
</div>
|
||
|
||
|
||
<div id="mplus-logo" class="years-25">
|
||
<a href="https://medlineplus.gov/">
|
||
<img alt="MedlinePlus Trusted Health Information for You" title="MedlinePlus Trusted Health Information for You" src="https://medlineplus.gov/images/m_logo_25.png"/>
|
||
</a>
|
||
</div>
|
||
|
||
|
||
<div id="mplus-nav">
|
||
|
||
<div aria-live="polite" class="sm-live-area hide-offscreen"></div>
|
||
<button id="sm-menu-btn" class="navmenu-btn" title="Menu" role="button" aria-controls="mplus-menu-list" type="submit">Menu<span class="icon icon-nav-menu"></span></button>
|
||
<ul id="mplus-menu-list" class="nav-list">
|
||
<li><a href="https://medlineplus.gov/healthtopics.html">Health Topics</a></li>
|
||
<li><a href="https://medlineplus.gov/druginformation.html">Drugs & Supplements</a></li>
|
||
<li><a href="https://medlineplus.gov/genetics/">Genetics</a></li>
|
||
<li><a href="https://medlineplus.gov/lab-tests/">Medical Tests</a></li>
|
||
<li><a href="https://medlineplus.gov/encyclopedia.html">Medical Encyclopedia</a></li>
|
||
<li><a href="https://medlineplus.gov/about/">About MedlinePlus</a></li>
|
||
</ul><button id="sm-search-btn" class="navmenu-btn" title="Search" role="button" aria-controls="mplus-search" type="submit"><span class="hide-offscreen"></span>Search<span class="icon icon-nav-search"></span></button>
|
||
|
||
<div class="top-1">
|
||
|
||
<form id="mplus-search" method="get" action="https://vsearch.nlm.nih.gov/vivisimo/cgi-bin/query-meta" title="Search MedlinePlus" target="_self">
|
||
|
||
<input type="hidden" name="v:project" value="medlineplus"/>
|
||
<input type="hidden" name="v:sources" value="medlineplus-bundle"/>
|
||
|
||
<div class="form-box text-combo">
|
||
<div class="form-area"><label class="hide-offscreen" for="searchtext_primary">Search MedlinePlus</label>
|
||
<input id="searchtext_primary" class="form-text" type="text" placeholder="Search MedlinePlus" alt="#Site Search input" title="Site Search input" maxlength="400" size="40" name="query" autocomplete="off" role="textbox" aria-autocomplete="list" aria-haspopup="true"/>
|
||
</div>
|
||
<div class="button-area">
|
||
<button class="form-btn" title="Search MedlinePlus" alt="Search MedlinePlus" type="submit">GO</button>
|
||
</div>
|
||
</div>
|
||
</form>
|
||
|
||
<div class="secondarynav">
|
||
<ul class="nav-list">
|
||
<li><a href="https://medlineplus.gov/about/"><span>About MedlinePlus</span></a></li>
|
||
<li><a href="https://medlineplus.gov/whatsnew/">What's New</a></li>
|
||
<li><a href="https://medlineplus.gov/sitemap.html"><span>Site Map</span></a></li>
|
||
|
||
|
||
<li><a href="https://support.nlm.nih.gov/knowledgebase/category/?id=CAT-01231&category=medlineplus&from=https%3A//medlineplus.gov/genetics/understanding/traits/handedness/" target="_blank"><span>Customer Support</span></a></li>
|
||
|
||
</ul>
|
||
</div>
|
||
|
||
</div>
|
||
<div id="mplus-nav-bar">
|
||
<ul class="nav-list">
|
||
<li><a href="https://medlineplus.gov/healthtopics.html">Health Topics</a></li><li><a href="https://medlineplus.gov/druginformation.html">Drugs & Supplements</a></li><li><a href="https://medlineplus.gov/genetics/">Genetics</a></li><li><a href="https://medlineplus.gov/lab-tests/">Medical Tests</a></li><li><a href="https://medlineplus.gov/encyclopedia.html">Medical Encyclopedia</a></li>
|
||
</ul>
|
||
</div>
|
||
|
||
|
||
<a id="mplus-lang-toggle" href="https://medlineplus.gov/spanish/genetica/entender/rasgos/destreza/" title="Español">Español</a>
|
||
|
||
</div>
|
||
</div>
|
||
</header>
|
||
|
||
<div id="mplus-content">
|
||
|
||
<div id="breadcrumbs">
|
||
<div itemprop="breadcrumb" itemscope="" itemtype="http://schema.org/BreadcrumbList">
|
||
<span class="hide-offscreen">You Are Here:</span>
|
||
<div itemscope itemprop="itemListElement" itemtype="http://schema.org/ListItem">
|
||
<a href="https://medlineplus.gov/" itemprop="item"><span itemprop="name">Home</span></a>
|
||
→
|
||
<meta itemprop="position" content="1"/>
|
||
</div>
|
||
|
||
|
||
<div itemscope itemprop="itemListElement" itemtype="http://schema.org/ListItem">
|
||
<a href="https://medlineplus.gov/genetics/" itemprop="item"><span itemprop="name">Genetics</span></a>
|
||
→
|
||
<meta itemprop="position" content="2"/>
|
||
</div>
|
||
|
||
|
||
|
||
<div itemscope itemprop="itemListElement" itemtype="http://schema.org/ListItem">
|
||
<a href="https://medlineplus.gov/genetics/understanding/" itemprop="item"><span itemprop="name">Help Me Understand Genetics</span></a>
|
||
→
|
||
<meta itemprop="position" content="3"/>
|
||
</div>
|
||
|
||
|
||
|
||
<div itemscope itemprop="itemListElement" itemtype="http://schema.org/ListItem">
|
||
<a href="https://medlineplus.gov/genetics/understanding/traits/" itemprop="item"><span itemprop="name">Genetics and Human Traits</span></a>
|
||
→
|
||
<meta itemprop="position" content="4"/>
|
||
</div>
|
||
|
||
|
||
|
||
<div>
|
||
<span>Is handedness determined by genetics?</span>
|
||
</div>
|
||
|
||
|
||
</div>
|
||
</div>
|
||
<span class="page-url print-only">URL of this page: https://medlineplus.gov/genetics/understanding/traits/handedness/</span>
|
||
|
||
<div >
|
||
|
||
<article>
|
||
<div class="page-info">
|
||
<div class="page-title">
|
||
<a name="start" id="start"></a>
|
||
<h1>Is handedness determined by genetics?</h1>
|
||
</div>
|
||
<div class="page-actions"></div>
|
||
<noscript><span class="js-disabled-message">To use the sharing features on this page, please enable JavaScript.</span></noscript>
|
||
</div>
|
||
|
||
<div class="main">
|
||
|
||
<section><div class="mp-content"><p>Like most aspects of human traits, handedness is <a data-pid="20135" href="https://medlineplus.gov/genetics/understanding/mutationsanddisorders/complexdisorders/">complex</a> and appears to be influenced by multiple factors, including genetics and environment.</p>
|
||
<p>Handedness, or hand preference, is the tendency to be more skilled and comfortable using one hand instead of the other for tasks such as writing and throwing a ball. Although the percentage varies worldwide, in Western countries, 85 to 90 percent of people are right-handed and 10 to 15 percent of people are left-handed. Mixed-handedness (preferring different hands for different tasks) and ambidextrousness (the ability to perform tasks equally well with either hand) are uncommon.</p>
|
||
<p>Hand preference becomes increasingly apparent in early childhood and tends to be consistent throughout life. However, little is known about its biological basis. Hand preference probably arises as part of the developmental process that differentiates the right and left sides of the body (called right-left asymmetry). More specifically, handedness appears to be related to differences between the right and left halves (<a class="image-modal" data-alt="Front view of the brain with the right and left cerebral hemispheres, cerebellum, and brain stem labeled." data-caption="" data-credit="National Institute on Aging/National Institutes of Health" data-filepath="images/PX00003S_PRESENTATION.jpeg" data-imgtype="genetics" data-lang="us" data-pix="PX00003S" data-sourceurl="https://www.flickr.com/photos/nihgov/sets/72157663368688842" data-title="Front view of brain" href="https://medlineplus.gov/images/PX00003S_PRESENTATION.jpeg" id="PX00003S_2" title="Show image">hemispheres<img alt="" class="image-modal-icon" src="https://medlineplus.gov/css/img/icon_camera_small.png"/></a>) of the brain. The right hemisphere controls movement on the left side of the body, while the left hemisphere controls movement on the right side of the body.</p>
|
||
<p>It was initially thought that a single gene controlled handedness. However, more recent studies suggest that multiple genes, perhaps up to 40, contribute to this trait. Each of these genes likely has a weak effect by itself, but together they play a significant role in establishing hand preference. Studies suggest that at least some of these genes help determine the overall right-left asymmetry of the body starting in the earliest stages of development. So far, researchers have identified only a few of the many genes thought to influence handedness.
|
||
Studies suggest that other factors also contribute to handedness. The prenatal environment and cultural influences may play a role. </p>
|
||
<p>Like many complex traits, handedness does not have a simple pattern of inheritance. Children of left-handed parents are more likely to be left-handed than are children of right-handed parents. However, because the overall chance of being left-handed is relatively low, most children of left-handed parents are right-handed. Identical twins are more likely than non-identical twins (or other siblings) to both be right-handed or left-handed, but many twins have opposite hand preferences.</p>
|
||
<h2>Scientific journal articles for further reading</h2>
|
||
<p>Armour JA, Davison A, McManus IC. Genome-wide association study of handedness excludes simple genetic models. Heredity (Edinb). 2014 Mar;112(3):221-5. doi:10.1038/hdy.2013.93. Epub 2013 Sep 25. PubMed: <a href="https://www.ncbi.nlm.nih.gov/pubmed/24065183" target="_blank">24065183</a>. Free full-text available from PubMed Central: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3931166/" target="_blank">PMC3931166</a>.</p>
|
||
<p>Brandler WM, Morris AP, Evans DM, Scerri TS, Kemp JP, Timpson NJ, St Pourcain B, Smith GD, Ring SM, Stein J, Monaco AP, Talcott JB, Fisher SE, Webber C, Paracchini S. Common variants in left/right asymmetry genes and pathways are associated with relative hand skill. PLoS Genet. 2013;9(9):e1003751. doi: 10.1371/journal.pgen.1003751. Epub 2013 Sep 12. PubMed: <a href="https://www.ncbi.nlm.nih.gov/pubmed/24068947" target="_blank">24068947</a>. Free full-text available from PubMed Central: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772043/" target="_blank">PMC3772043</a>.</p>
|
||
<p>Brandler WM, Paracchini S. The genetic relationship between handedness and neurodevelopmental disorders. Trends Mol Med. 2014 Feb;20(2):83-90. doi: 10.1016/j.molmed.2013.10.008. Epub 2013 Nov 23. Review. PubMed: <a href="https://www.ncbi.nlm.nih.gov/pubmed/24275328" target="_blank">24275328</a>. Free full-text available from PubMed Central: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969300/" target="_blank">PMC3969300</a>
|
||
</p>
|
||
<p>de Kovel CGF, Francks C. The molecular genetics of hand preference revisited. Sci Rep. 2019 Apr 12;9(1):5986. doi: 10.1038/s41598-019-42515-0. PubMed: <a href="https://www.ncbi.nlm.nih.gov/pubmed/30980028" target="_blank">30980028</a>; Free full-text available from PubMed Central: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6461639/" target="_blank">PMC6461639</a>.</p>
|
||
<p>McManus IC, Davison A, Armour JA. Multilocus genetic models of handedness closely resemble single-locus models in explaining family data and are compatible with genome-wide association studies. Ann N Y Acad Sci. 2013 Jun;1288:48-58. doi:10.1111/nyas.12102. Epub 2013 Apr 30. PubMed: <a href="https://www.ncbi.nlm.nih.gov/pubmed/23631511" target="_blank">23631511</a>. Free full-text available from PubMed Central: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4298034/" target="_blank">PMC4298034</a>.</p></div>
|
||
</section>
|
||
|
||
</div>
|
||
|
||
<div class="side">
|
||
<aside>
|
||
|
||
<section><div class="side-section"><div class="mp-content"><div class="section-header long-header"><h2>To find out more about how handedness is determined:</h2></div><div class="section-body"><p>The Washington State Twin Registry has an FAQ about <a href="https://wstwinregistry.org/2015/10/01/do-identical-twins-always-have-the-same-hand-preference/" target="_blank">hand preference in identical twins</a>.</p>
|
||
</div></div>
|
||
</div></section>
|
||
|
||
</aside>
|
||
</div>
|
||
|
||
|
||
<div class="bottom">
|
||
|
||
<section><div class="mp-exp mp-content"><h2>Topics in the Genetics and Human Traits chapter</h2><ul><li><a data-pid="20179" href="https://medlineplus.gov/genetics/understanding/traits/fingerprints/">Are fingerprints determined by genetics?</a></li><li><a data-pid="20181" href="https://medlineplus.gov/genetics/understanding/traits/eyecolor/">Is eye color determined by genetics?</a></li><li><a data-pid="20183" href="https://medlineplus.gov/genetics/understanding/traits/intelligence/">Is intelligence determined by genetics?</a></li><li>Is handedness determined by genetics?</li><li><a data-pid="20187" href="https://medlineplus.gov/genetics/understanding/traits/twins/">Is the probability of having twins determined by genetics?</a></li><li><a data-pid="20189" href="https://medlineplus.gov/genetics/understanding/traits/hairtexture/">Is hair texture determined by genetics?</a></li><li><a data-pid="20191" href="https://medlineplus.gov/genetics/understanding/traits/haircolor/">Is hair color determined by genetics?</a></li><li><a data-pid="20193" href="https://medlineplus.gov/genetics/understanding/traits/height/">Is height determined by genetics?</a></li><li><a data-pid="20195" href="https://medlineplus.gov/genetics/understanding/traits/moles/">Are moles determined by genetics?</a></li><li><a data-pid="20197" href="https://medlineplus.gov/genetics/understanding/traits/dimples/">Are facial dimples determined by genetics?</a></li><li><a data-pid="20199" href="https://medlineplus.gov/genetics/understanding/traits/athleticperformance/">Is athletic performance determined by genetics?</a></li><li><a data-pid="20201" href="https://medlineplus.gov/genetics/understanding/traits/longevity/">Is longevity determined by genetics?</a></li><li><a data-pid="20203" href="https://medlineplus.gov/genetics/understanding/traits/temperament/">Is temperament determined by genetics?</a></li></ul><p><a data-pid="20081" href="https://medlineplus.gov/genetics/understanding/">Other chapters in Help Me Understand Genetics</a></p></div>
|
||
</section>
|
||
|
||
<section>
|
||
<!--
|
||
<div class="from-ghr">
|
||
<img src="https://medlineplus.gov/images/fromGHR.png" alt="From Genetics Home Reference" />
|
||
<p>Genetics Home Reference has merged with MedlinePlus. Genetics Home Reference content now can be found in the "Genetics" section of MedlinePlus. <a href="https://medlineplus.gov/about/general/genetics/newhome/">Learn more</a></p>
|
||
</div>
|
||
-->
|
||
|
||
|
||
<p>The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.</p>
|
||
|
||
</section>
|
||
|
||
</div>
|
||
|
||
</article>
|
||
|
||
</div>
|
||
|
||
|
||
<div id="citation-how-to">
|
||
<button><span>Learn how to cite this page</span></button>
|
||
</div>
|
||
|
||
</div>
|
||
|
||
<footer>
|
||
<div id="mplus-footer">
|
||
<div class="footer1">
|
||
|
||
<ul class="secondarynav">
|
||
<li><a href="https://medlineplus.gov/about/">About MedlinePlus</a></li>
|
||
<li><a href="https://medlineplus.gov/whatsnew/">What's New</a></li>
|
||
<li><a href="https://medlineplus.gov/sitemap.html">Site Map</a></li>
|
||
|
||
|
||
<li><a href="https://support.nlm.nih.gov/knowledgebase/category/?id=CAT-01231&category=medlineplus&from=https%3A//medlineplus.gov/genetics/understanding/traits/handedness/" target="_blank"><span>Customer Support</span></a></li>
|
||
|
||
</ul>
|
||
|
||
<ul class="follow-footer">
|
||
<li>
|
||
<a href="https://medlineplus.gov/rss.html" class="follow-item">Subscribe to RSS<img src="https://medlineplus.gov/images/feed.png" class="social-media-toolkit-icon" alt="RSS" title="RSS"></a>
|
||
</li>
|
||
<li>
|
||
<span class="follow-label">Follow us</span>
|
||
<a href="https://twitter.com/medlineplus" class="follow-item" target="_blank">
|
||
<img src="https://medlineplus.gov/images/i_share_twitter.png" class="follow-icon" alt="X" title="X">
|
||
</a>
|
||
<a href="https://facebook.com/Mplus.gov/" class="follow-item" target="_blank">
|
||
<img src="https://medlineplus.gov/images/i_share_fb.png" class="follow-icon" alt="Facebook" title="Facebook">
|
||
</a>
|
||
<a href="https://www.instagram.com/mplusgov/" class="follow-item" target="_blank">
|
||
<img src="https://medlineplus.gov/images/Instagram_Glyph_Gradient_RGB.png" class="follow-icon" alt="Instagram" title="Instagram">
|
||
</a>
|
||
</li>
|
||
<li>
|
||
<a href="https://medlineplus.gov/social-media-toolkit/" class="social-media-toolkit-item">Social Media Toolkit<img src="https://medlineplus.gov/images/i_social_media_toolkit.png" class="social-media-toolkit-icon" alt="Social Media Toolkit" title="Social Media Toolkit"></a>
|
||
</li>
|
||
</ul>
|
||
</div>
|
||
|
||
<div class="footer2">
|
||
<ul>
|
||
|
||
|
||
<li><a href=" https://www.nlm.nih.gov/web_policies.html" target='_blank'>NLM Web Policies</a></li>
|
||
|
||
<li><a href="https://medlineplus.gov/about/using/usingcontent/" >Copyright</a></li>
|
||
|
||
<li><a href="https://medlineplus.gov/accessibility.html">Accessibility</a></li>
|
||
<li><a href="https://medlineplus.gov/about/using/criteria/">Guidelines for Links</a></li>
|
||
<li><a href="https://medlineplus.gov/plugins.html">Viewers & Players</a></li>
|
||
<li><a href="https://www.hhs.gov/vulnerability-disclosure-policy/index.html" target="_blank">HHS Vulnerability Disclosure</a></li>
|
||
|
||
<li><a href="https://medlineplus.gov/medlineplus-connect/">MedlinePlus Connect for EHRs</a></li>
|
||
<li><a href="https://medlineplus.gov/about/developers/">For Developers</a></li>
|
||
|
||
</ul>
|
||
|
||
<div class="address">
|
||
<a href="https://www.nlm.nih.gov" target="_blank">National Library of Medicine</a>
|
||
<span>8600 Rockville Pike, Bethesda, MD 20894</span>
|
||
<a href="https://www.hhs.gov" target="_blank">U.S. Department of Health and Human Services</a>
|
||
<a href="https://www.nih.gov" target="_blank">National Institutes of Health</a>
|
||
|
||
</div>
|
||
|
||
|
||
<div class="date">
|
||
|
||
|
||
|
||
<span id="lastupdate">Last updated July 8, 2022</span>
|
||
|
||
|
||
|
||
</div>
|
||
|
||
|
||
<div class="return-top"><a href="#top" title="Return to top"><img class="return-top-icon" alt="Return to top" src="https://medlineplus.gov/images/return-top.png"></a></div>
|
||
</div>
|
||
</div>
|
||
</footer>
|
||
</div>
|
||
|
||
|
||
<script src="https://medlineplus.gov/jslib/jquery-3.6.0.min.js" type="text/javascript"></script>
|
||
<script src="https://medlineplus.gov/jslib/mplus-frontend-controls-new.js" type="text/javascript"></script>
|
||
<script src="https://medlineplus.gov/jslib/mplus-share.js?id=1112022" type="text/javascript"></script>
|
||
<!--[if lte IE 9]><script src="//www.nlm.nih.gov/medlineplus/jslib/jquery.placeholder.js" type="text/javascript"></script><![endif]-->
|
||
<script src="https://medlineplus.gov/jslib/control.js" type="text/javascript"></script>
|
||
<script src="https://medlineplus.gov/uswds/js/uswds.min.js" type="text/javascript"></script>
|
||
|
||
|
||
|
||
|
||
|
||
</body>
|
||
</html>
|