Transgenes can be made dominant in genetically engineered organisms by inserting them into germ cells, ensuring that offspring inherit the desired traits. The dominance or recessiveness of an allele is determined by its biochemical function, with gain-of-function alleles typically being dominant and loss-of-function alleles usually recessive. However, there are exceptions, such as dominant negative alleles that can disrupt the function of the wild type allele. Understanding these genetic principles is crucial for effective genetic engineering. This knowledge can guide the development of organisms with specific, inheritable characteristics.