c. The Lu(a-b-) phenotype can be caused by two different genetic situations. It
can be produced by either one independently segregating dominant gene or
homozygosity at the Lutheran locus for amorphic genes. The name In(Lu) has been
suggested for the rare inhibitor gene that prevents normal expression of the Lutheran
genes in the dominant Lu(a-b-) phenotype.
d. Lutheran system antibodies are rare, and there is very little evidence that they
have ever caused hemolytic transfusion reactions or hemolytic disease of the newborn.
Most examples of anti-Lua and some anti-Lub will agglutinate saline-suspended red
blood cells, causing small-to-moderate-sized, loosely agglutinated clumps of cells
superimposed on a background of unagglutinated red blood cells. Most anti-Lub and
occasional anti-Lua react by the antiglobulin test.
e. Additional information is given in Tables 2-30 through 2-33.