app/views/user_mailer/genotyping_results.html.erb
<p>
the genetic data for the variation <%=@variation%> for <%=@phenotype_name%> you requested
<a href="<%="http://"+ActionMailer::Base.default_url_options[:host]+@link%>">
for download from openSNP are now available in a zipped format.
</a>
</p>
<p>
Have fun with it!
</p>