There is a very complex relationship between genes, traits and diseases. the most primitive way to decipher this relationship is the gene linkage analysis established in the middle of the last century: by comparing the similarities and differences of chromosome bands or genetic markers of different members of families affected by genetic diseases, locate disease-causing genes on chromosomes. This method has made a lot of achievements in the study of single-gene genetic diseases, but its disadvantage is that the resolution is limited, so it is difficult to accurately locate a single gene.
The main content of this text is that there are obvious defects in the method of gene linkage analysis.