Cytogenetics is a discipline that study the structure and number of chromosomes including their morphology, position of the centromere, arm length, staining bands, etc. These features can be observed by microscope and enable us to identify different genome rearrangements (i.e., translocations, deletions, centric fusion, chromosome duplications, etc.) by ilustrating chromosomes in defined pictures referred to as karyotypes. In consequence, they are chromosome features that can be used in order to categorize different samples.
The beta globin protein is one of the subunits of hemoglobin, a protein necessary for the oxygen-carrying function of red blood cells. People with the sickle cell mutation in both copies of the HBB gene produce proteins that clump together and lead to changes in the shape and behavior of red blood cells.