Genetic variants are most often either dominant or recessive. In the dominant case, only one copy of a non-functioning gene will need to be inherited by a person for them to have a genetic condition. In contrast, in most cases, a person will need to inherit two mutations, one from the mother and one from the father, in order to be affected. If each parent has only one copy of the gene, there is a 25% chance that the child will inherit the condition. An exception to this occurs in conditions that are linked to the sex chromosomes. Certain conditions are more often expressed in males compared to females because they possess only one X and one Y chromosome.
What is the difference between a dominant and recessive genetic variant?
