Pedigree of index case (arrow). Figures beneath each member of kindred re-present activities of G6PDH. Note the index case has no measurable G6PD, although she has two sons with normal G6PD activities. Older daughter of index case has erythrocyte G6PD level which is at lower limit of normal. She may also be heterozygote, although this cannot be established at present. (From: Trujillo J, The Lancet 1961;ii:1445, with permission from Elsevier.⁵²)