Hemoglobin Hopkins-2 was originally reported to contain two abnormalαchains. Both had aspartic acid instead of the normal histidine at positionα112; the second a chain also contained two additional amino acid substitutions. In subsequent reports of the structure of this hemoglobin, only the His→Asp substitution was found. To determine whether the second abnormal a chain was limited to the original kindred, the structure of their hemoglobin was redetermined. Only the His→Asp substitution was present.