The purpose of this study is to determine the mechanisms that regulate human globin gene expression by analyzing the function of cell signaling pathways and the expression of other related genes and their protein products in the bone marrow cells of people without blood diseases. This includes the effects of drugs and other in vitro manipulations of the cells once they are removed from donors. These assays will include, but are not limited to, determinations of DNA methylation status, histone acetylation profiles, DNAse sensitivity, transcription factor binding to DNA, levels of various proteins, messenger RNAs and miRNAs in the cells of the marrow samples. By understanding how this process occurs in people without blood diseases, we hope to to design future treatments for people with diseases such as sickle cell disease and B-thalassemia.