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A variant of type B blood was found in three members of a family from El Salvador. In two members, both genotype BO, the blood and saliva had the characteristics of the phenotype Be1 . In the third member, genotype A2B, the red cell B antigen was stronger than in his BO genotype relatives. Thus, in this family, the presence of the A2 gene appeared to enhance the expression of the B gene.

An antibody against a low-incidence antigen was detected in the serum of a woman whose newborn infant was found to have a positive direct antiglobulin test. The antibody failed to agglutinate 79 examples of red cells having low-incidence antigens and 16 examples of high-incidence antigen-negative red cells. The woman's serum reacted strongly with her husband's red cells in the antiglobulin test and with 5 of 6 Er(a-) cell samples from unrelated donors, suggesting that the antigen has an antithetical relationship to Era. The failure of the serum to react with one Er(a-) cell sample and with cells from the Er(a+) daughter of an Er(a-b+) mother gives evidence for a silent allele, Er. Four Er(b+) bloods were found among 605 random white donors, indicating a gene frequency for Erb of 0.0033.

An evaluation was made of the variation and importance of dropper volume delivery on pretransfusion testing in ten hospital transfusion services which annually perform a combined total of 225,000 compatibility tests on the serum of approximately 70,000 patients. The pretransfusion testing by these institutions typifies practices throughout the United States in that serum and red blood cells are used with little awareness of actual volumes used and the resultant proportion of one reactant to the other. Tests of the hospitals' dropper pipettes showed a range of serum delivery per test of 0.0465 to 0.1155 ml. Commercial reagent red blood cell vial droppers delivered (according to cell concentration) from 0.00166 to 0.00294 ml packed red blood cells (pcv). From these findings, it could be shown that the serum to cell ratio in the tests done in two transfusion services was as low as 19 to 1 and that the highest ratio of 70 to 1 was used in only one institution. In none was the serum-cell ratio the optimum of 80 to 1.

A 61-year-old nulliparous woman who had never been transfused was admitted to the hospital because of severe anemia. She had been treated with gold salts for 4.5 years for rheumatoid arthritis. Because she had a negative direct antiglobulin test, an anti-Ge found in her serum was believed to be an alloantibody. Subsequent testing of her initial serum sample with autologous red cells drawn 12 months later showed them to be strongly agglutinated, indicating that she had had a transient depression of her Ge antigen and that the anti-Ge was an autoantibody. It was postulated that these transient effects may have been related to the gold therapy.