Question: Harvey Itano used electrophoresis to demonstrate the difference between normal hemoglobin and sickle cell hemoglobin in collaboration with a chemist born in what year?
Context: "Sickle Cell Anemia, a Molecular Disease" is a 1949 scientific paper by Linus Pauling, Harvey A. Itano, Seymour J. Singer and Ibert C. Wells that established sickle-cell anemia as a genetic disease in which affected individuals have a different form of the metalloprotein hemoglobin in their blood.  The paper, published in the November 25, 1949 issue of "Science", reports a difference in electrophoretic mobility between hemoglobin from healthy individuals and those with sickle-cell anemia, with those with sickle cell trait having a mixture of the two types.  The paper suggests that the difference in electrophoretic mobility is probably due to a different number of ionizable amino acid residues in the protein portion of hemoglobin (which was confirmed in 1956 by Vernon Ingram), and that this change in molecular structure is responsible for the sickling process.  It also reports the genetic basis for the disease, consistent with the simultaneous genealogical study by James V. Neel: those with sickle-cell anemia are homozygous for the disease gene, while heterozygous individuals exhibit the usually asymptomatic condition of sickle cell trait. Red blood cells (erythrocytes) from donors contain normal hemoglobin (HbA), and transfusion of normal red blood cells into people with sickle cell disease reduces the percentage of red cells in the circulation containing the abnormal hemoglobin (HbS).  Although transfusion of donor red blood cells can ameliorate and even prevent complications of sickle cell disease in certain circumstances, transfusion therapy is not universally beneficial in sickle cell disease. A CO-oximeter is a device that measures the oxygen carrying state of hemoglobin in a blood specimen, including oxygen-carrying hemoglobin (O2Hb), non-oxygen-carrying but normal hemoglobin (HHb) (formerly, but incorrectly, referred to as 'reduced' hemoglobin), as well as the dyshemoglobins such as carboxyhemoglobin (COHb) and methemoglobin (MetHb).  The use of 'CO' rather than 'Co' or 'co' is more appropriate since this designation represents a device that measures carbon monoxide (CO) bound to hemoglobin, as distinguished from simple oximetry which measures hemoglobin bound to molecular oxygen—O2Hb—or hemoglobin capable of binding to molecular oxygen—HHb.  Simpler oximeters may report oxygen saturation alone, i.e. the ratio of oxyhemoglobin to total 'bindable' hemoglobin (i.e. oxyhemoglobin + deoxyhemoglobin-HHb). Harvey Akio Itano (November 3, 1920 – May 8, 2010) was an American biochemist best known for his work on the molecular basis of sickle cell anemia and other diseases.  In collaboration with Linus Pauling, Itano used electrophoresis to demonstrate the difference between normal hemoglobin and sickle cell hemoglobin; their 1949 paper "Sickle Cell Anemia, a Molecular Disease" (coauthored also with S. J. Singer and Ibert C. Wells) was a landmark in both molecular medicine and protein electrophoresis. Linus Carl Pauling (February 28, 1901 – August 19, 1994) was an American chemist, biochemist, peace activist, author, and educator.  He published more than 1,200 papers and books, of which about 850 dealt with scientific topics. " New Scientist" called him one of the 20 greatest scientists of all time, and as of 2000, he was rated the 16th most important scientist in history. Hemoglobin electrophoresis is a blood test that can detect different types of hemoglobin.  It uses the principles of gel electrophoresis to separate out the various types of hemoglobin and is a type of native gel electrophoresis.  The test can detect abnormal levels of HbS, the form associated with sickle-cell disease, as well as other abnormal hemoglobin-related blood disorders, such as beta thalassaemia and hemoglobin C.  It can also be used to determine whether there is a deficiency of any normal form of hemoglobin, as in the group of diseases known as thalassemias. Different hemoglobins have different charges, and according to those charges and the amount, hemoglobins move at different speeds in the gel whether in alkaline gel or acid gel.The hemoglobin electrophoresis is also known to be thalessemia screening, this also can be helpful for the patient who is frequently need of fresh blood transfusion.  The patient needs blood transfusion because the body is unable to produce enough hemoglobin to satisfy the body's requirement. (See Migration Patterns).  Electrophoresis is done by the use of cellulose acetate.  After running electrophoresis at 150 to 200 volt, stain the cellulose acetate gel with Ponceau red.  Thalassemia major Hb F level and Hb A2 levels increase. Glycated hemoglobin (hemoglobin A1c, HbA, A1C, or Hb; sometimes also referred to as being Hb1c or HGBA1C) is a form of hemoglobin that is measured primarily to identify the three-month average plasma glucose concentration.  The test is limited to a three-month average because the lifespan of a red blood cell is four months (120 days).  However, since RBCs do not all undergo lysis at the same time, HbA1C is taken as a limited measure of 3 months.  It is formed in a non-enzymatic glycation pathway by hemoglobin's exposure to plasma glucose.  HbA is a measure of the beta-N-1-deoxy fructosyl component of hemoglobin.  The origin of the naming derives from Hemoglobin type A being separated on cation exchange chromatography.  The first fraction to separate, probably considered to be pure Hemoglobin A, was designated HbA, the following fractions were designated HbA, HbA, and HbA, respective of their order of elution.  There have subsequently been many more sub fractions as separation techniques have improved.  Normal levels of glucose produce a normal amount of glycated hemoglobin.  As the average amount of plasma glucose increases, the fraction of glycated hemoglobin increases in a predictable way.  This serves as a marker for average blood glucose levels over the previous three months before the measurement as this is the lifespan of red blood cells. Hypochromic anemia is a generic term for any type of anemia in which the red blood cells (erythrocytes) are paler than normal.  ("Hypo"- refers to "less", and "chromic" means "color".)  A normal red blood cell will have an area of pallor in the center of it; it is biconcave disk shaped.  In hypochromic cells, this area of central pallor is increased.  This decrease in redness is due to a disproportionate reduction of red cell hemoglobin (the pigment that imparts the red color) in proportion to the volume of the cell.  Clinically the color can be evaluated by the Mean Corpuscular Hemoglobin (MCH) or Mean Corpuscular Hemoglobin Concentration (MCHC).  The MCHC is considered the better parameter of the two as it adjusts for effect the size of the cell has on its color.  Hypochromia is clinically defined as below the normal MHC reference range of 27-33 picograms/cell in adults or below the normal MCHC reference range of 33-36 g/dL in adults. Sickle cell trait describes a condition in which a person has one abnormal allele of the hemoglobin beta gene (is heterozygous), but does not display the severe symptoms of sickle-cell disease that occur in a person who has two copies of that allele (is homozygous).  Those who are heterozygous for the sickle cell allele produce both normal and abnormal hemoglobin (the two alleles are codominant with respect to the actual concentration of hemoglobin in the circulating cells). Hemoglobin A3 is a predominantly historic term for a fraction of normal hemoglobin molecules that is seen when hemoglobin is separated out using starch block electrophoresis.  These Hemoglobin molecules are non-enzymatic modifications of the hemoglobin molecules and they encompass hemoglobin, Hb (both the subtypes Hb and Hb) and Hb.
Answer: 1901