The Murayama Test. Part II. Principles, Technique, Interpretation, and Data

The Murayama Test is based on the molecular mechanism of sickling for S hemoglobin as proposed and recently modified by Murayama. The principle of the test is predicated on a feature of molecular structure: hydrophobic bonds formed between interacting tetramers by the substituted no. 6 Valine near the N-terminal end of each beta-S globin chain, which are essential to the sickling event in S hemoglobin. The existence of these particular hydrophobic bonds can be visually signaled in deoxygenated, concentrated hemolysates by reversible, thermally dependent gel-sol transformations. Under the conditions of the Murayama Test such a demonstration is specific for S hemoglobin or the S structural variant, hemoglobin C (Harlem). The test: (1) is simple; (2) has clear end points; (3) will detect both homozygous and heterozygous S hemoglobin; and (4) is specific. The technique of the test is recorded. The specificity of the Murayama Test is shown to reside in particular molecular structural features of the hemoglobin tetramers of S, C (Harlem), C (Georgetown), and I (all sickling hemoglobinopathies). Data from 29 cases of S hemoglobin and 37 controls are reported. The close agreement between Murayama's hypothesis for sickling in S hemoglobin and the experimental data and analysis presented in this report lends additional support for his views. (Author)