“…At 8 weeks of therapy, his scars had thinned and become less prominent, and his parents report they had to start trimming his fingernails again, which they had not done for some time.4 | DISCUSSIONTo better understand the range of PDGFRB phenotypes, we per-formed detailed genotype-phenotype analysis on a cohort of 74 individuals with known or presumed mutations of PDGFRB, including the 12 individuals reported here and another 62 for whom individuallevel data were provided in prior reports. The cohort included 46 individuals with confirmed PDGFRB pathogenic GOF variants, a PDGFRB+ group (AlQawahmed et al, 2019;Arts et al, 2016;Brasseur et al, 2010;Bredrup et al, 2019;Cheung et al, 2013;Frezin et al, 2015;Gawli nski et al, 2018;Guimier et al, 2019;Johnston et al, 2015;Karasozen et al, 2019;Lepelletier et al, 2017;Minatogawa et al, 2017;Mudry et al, 2017;Murray et al, 2017;Penttinen, Niemi, Vinkka-Puhakka, Johansson, & Aula, 1997;Pond et al, 2018;Takenouchi et al, 2015;Zarate et al, 2019;Zhang et al, 2018;Zufferey et al, 2013), and another 28 with phenotype data only, mostly from older reports-a PDGFRB-S or suspected group(Guimier et al, 2019;Hausbrandt et al, 2010;Holzer-Fruehwald, Blaser, Rossi, Fruehwald-Pallamar, & Thurnher, 2012;Kaplan, Ojemann, Grange, Fuller, & Park, 2002;Kulkarni, Desai, Grundy, & Sergi, 2012;Pelluard-Nehmé et al, 2007;Spadola, Anooshiravani, Sayegh, Jequier, & Hanquinet, 2002). For the purposes of this analysis, we excluded the three individuals with unicentric Castleman disease with PDGFRB variants in affected lymph nodes, as 91% of individuals with unicentric Castleman disease were not found to harbor PDGFRB variants, and several other pathogenic variants were identified in affected tissue of other patients with the same phenotype(Li et al, 2019).4.1 | Phenotype analysis...…”