However, according to an in silico study, NIS and TPO share homologous amino acid sequences with certain Borrelia and Yersinia proteins, including amino acid residues located at the binding motifs of the T-cell receptor (TCR) and several polymorphic variants of the HLA-DR locus (HLA-DR3, HLA-DR4, HLA-DR5, HLA-DR8, and HLA-DR9), some of which predispose not only to HT, but also to SS [63]. Here, TPO is linked to hematocrit.