The Expected “Bombay” Groups OhA1 and OhA2

An American family of English extraction is reported in which two Oh (“Bombay”) members have transmitted A 2 genes to their children thus demonstrating that the expression of the gene A 2 , like that of the gene B , can be suppressed in this phenotype. Another American family, of French extraction, shows with a high degree of probability that the expression of the gene A 1 can be similarly suppressed.