<p>There is some evidence that the ability to spell may have genetic influences: <a href=“A twin study of genetic influences on reading and spelling ability and disability - PubMed”>A twin study of genetic influences on reading and spelling ability and disability - PubMed;
but I can’t find anything more recent.</p>
<p>The most successful approach to spelling that I know of uses the “top words” approach, in which the most commonly used words are emphasized, rather than vocabulary and spelling being done together (which is a common approach). Knowing how to use your/you’re/yours, there/their/there’s/theirs, and it’s/its goes a long way toward solving common “spelling” problems, too. This is a list of the top 100 spelling errors: <a href=“http://www.yourdictionary.com/library/misspelled.html[/url]”>http://www.yourdictionary.com/library/misspelled.html</a></p>