If you have difficulty understanding how the gametes are formed, click on the REVIEW button below for return to the meiosis section where gene segregation is discussed. When two independently segregating genes are studied in the same cross, it is a dihybrid cross. A typical ratio of such a cross where the genes not only segregate independently of each other (that means they are on different chromosomes) but also function independently of each other, is a 9:3:3:1. Nine squares will contain at least one representative of each gene, A and B. Three squares will contain at least one A but no B. Three squares will contain at least one B but no A and one square will contain neither A nor B. Click on a square you believe contains at least an A and a B gene.
