Diagrammatic representation of regulation relationship between individuals in two families. The tvDTH-linked suppression response of PBMC from each individual to the antigen lysate from the family member is represented by a green arrows (regulation ≥ 25%) or pink arrow (regulation < 25%) with base of arrow by the PBMC donor and arrowhead pointing to antigen source. Individuals with dual green arrows between them are bidirectional pairs, where as those with a single or two pink arrows are uniregulatory or nonregulatory pairs. A, Rhesus Macaque family NIAID 8:H234 and DX9G are MHC-ID siblings (Mamu A002a, A018a; B001c, B002); Dam MHC type is A018a, A004; B002, B048; FG4V MHC is A002a, A018a; B012a, B002 and H644 is A002, A018a, B002 and B012b. B, human family FTX02. HLA type of Mother (green) is A2, 11; B7, 51; DR1, 4; HLA-Type of both the second oldest daughter (S2) and that of youngest male sibling (B4) is the same : A2, 32; B7, 27; DR1, 15; thus the differences in the response of the mother to these 2 HLA-identical offspring must be due to minor H differences between the two. The HLA type of the male sibling (B3) is A1, 11; B8, 51; Dr4, 17; and is identical to S2- A2, 32; B7, 27; DR1, 15. The letters M, B, and S represent mother, brother, and sister; the numbers represent the offspring birth order.