Both Chargaff Second Parity Rule and the Strand Symmetry Rule Are Imprecise

In order to check Chargaff Second Parity Rule, we find the strands are asymmetric in human DNA, this breaks the strand symmetry rule. We calculate the ratio between oligonucleotide ATGC and oligonucleotide CGTA, and we compare the sample sequence average ratio ATGC/CGTA and the complementary sequence average ratio ATGC/CGTA. we find evolution degree more bigger, then the strand symmetry deviation will be more bigger. sequence and its complementary strand sequence obviously have two different characters, include physical property, chemical property and biological property. It is very important, base on this asymmetry, we can find some new and special theories in biology to explain how chromosome communicates and works in the future. we also find, both leukemia and breast cancer are weakening the DNA’s asymmetry degree. Here need more research and check, maybe we can find an easy diagnosing method to leukemia and breast cancer, if this result here is right at last, it will benefit to the world