TSC2 and tuberous sclerosis: A TSC2 c.5024C>T, p.(Pro1675Leu) variant (VAF 2%) was identified in genomic DNA isolated from a shagreen patch that was the only clinical sign of TSC in subject 3.19, but not in genomic DNA isolated from peripheral blood or from fibroblasts cultured from a biopsy of normal skin, either by HaloPlex NGS or by AS-PCR.