<span>Erwin Chargaff's research found that there are two pairs of nucleotides in the DNA molecule, adenine-thymine, and guanine-cytosine. Those two pairs of nucleotides are complementary and since they pair up in the DNA molecule, the amount of one nucleotide in the pair must be equal to the amount of the other nucleotide of the pair. He also found that different species have different proportions of nucleotides, which proved that DNA is the carrier of genetic information, not the proteins.</span>
