Lethality and Interaction of Genes

Mendel's experiments discussed in the previous topic suggested that perhaps each character is controlled by a single factor or a single gene. One may get an idea from such results that a particular character is associated with a particular gene. However, a gene does not carry a character, but controls a developmental process. It is through an influence on the development that the gene brings about the desired effect on phenotype. It has also been shown that a gene may sometimes interfere with the development and may cause the death of the individual. Similarly, it was also discovered that the genes are not necessarily separate elements producing individually distinct effects. They may interact and produce a phenotype which may be the result of interaction of these genes.