Specifically, 10 Nef polymorphisms were reported in the French PAH group: the PxxP motif (proline-rich area essential for Nef interaction with SH3 domain-containing proteins122, where x is any amino acid), the L58V CD4 down-regulation domain94, the E63G acidic cluster mediating the sequestration of MHC-1 in the trans-Golgi network123, and the M79I/T80N/Y81F phosphorylation site for protein kinase C124. This evidence concerns the gene S100B and pulmonary arterial hypertension.