The specific variant is <i>FBN1</i> NM_000138.4 c.2953G > A p.(Gly985Arg).<h4>Conclusions</h4>We report a case of a previously undiagnosed Marfan syndrome death due to a <i>de novo FBN1</i> variant, c.2953G > A. This evidence concerns the gene FBN1 and Marfan syndrome.