The U.S. infant mortality rate generally declined throughout the 20th century, from 100 infant deaths per 1,000 live births in 1900 to 6.89 infant deaths per 1,000 live births in 2000.
hemoglobinopathies are genetic inherited disorders of hemoglobin the oxygen carrying protein of the red blood cells the hemoglobin molecule is composed of four separate polypeptide chains of amino acids two alpha chains and two beta chains as well as four iron bearing heme groups that bind oxygenemoglobinopathies are genetic inherited disorders of hemoglobin the oxygen carrying protein of the red blood cells the hemoglobin molecule is composed of four separate polypeptide chains of amino acids two alpha chains and two beta chains as well as four iron bearing heme groups that bind oxygen
Methemoglobinemia is a condition in which more than 1% of the hemoglobin in red blood cells takes the form of methemoglobin. Methemoglobulin is an abnormal form of hemoglobin (the molecule responsible for carrying oxygen in the blood cells) that is unable to bind to oxygen.utations in the HBB gene cause methemoglobinemia, beta-globin type. Hemoglobin consists of four protein subunits and four iron-containing molecules called heme. Heme molecules are necessary for red blood cells to pick up oxygen in the lungs and release oxygen to other cells in the body.