Any condition that results in the production of abnormal hemoglobin is included under the broad category of hemoglobinopathies. Worldwide, it is estimated that 7% of the population may carry a hemoglobinopathy with clinical significance.[12] The most well known condition in this group is sickle cell disease.[12] Newborn screening for a large number of hemoglobinopathies is done by detecting abnormal patterns using isoelectric focusing, which can detect many different types of abnormal hemoglobins.[12] In the United States, newborn screening for sickle cell disease was recommended for all infants in 1987, however it was not implemented in all 50 states until 2006.[12]