In the EXIST-2 trial, plasma VEGF-D and collagen IV levels were found to be potential prognostic as well as diagnostic biomarkers, and these results have been validated by subsequent studies not only in TSC-RAML (Dabora et al., 2011; Malinowska et al., 2013) but also in the TSC-LAM (Young et al., 2010; Xu et al., 2013; Amaral et al., 2019). The gene discussed is VEGFD; the disease is tuberous sclerosis.