has causal or contributing genetic variation HBB, GLU6VAL HBB, ASP73ASN Hemoglobin C-Harlem An abnormal hemoglobin in which two mutations occur in its beta-chains results in the sickling of red blood cells containing this hemoglobin. The sickling is the result of the mutation in which glutamic acid in position 6 is replaced by valine, which is not counteracted by the second mutation, in which the aspartic acid in position 73 is replaced by asparagine. https://www.omim.org/entry/141900#0243 Hemoglobin C-Georgetown Few but definitions not freely available Hemoglobin S-Hemoglobin C-Harlem HbS-HBC-Harlem SCDO (Jade Hotchkiss) Request inclusion into the HPO, below "Abnormal Hemoglobin"/"Sickling Hemoglobin with Two Beta-Globin Gene Substitutions". Sickling Hemoglobin with Two Beta-Globin Gene Substitutions