Failure to demonstrate dosage of U antigen.
Tests in which 11 examples of anti-U were used in titration studies against the red blood cells of 9 obligate Uu heterozygotes, from 4 unrelated families, and random Negro and Caucasian donors (many of whom were of the presumptive UU genotype) have failed to demonstrate any dosage of the U antigen.
D044383:Black People; D006579:Heterozygote; D006801:Humans; D008951:MNSs Blood-Group System; D044465:White People
D008951:MNSs Blood-Group System