Dominance (genetics)

One gene variant masking the effect of another in the other copy of the gene

In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The masking or overriding variant is said to be dominant and the other recessive. This state of having two different variants of the same gene, one on each copy of the chromosome, is originally caused by a mutation in one of the genes, either new (de novo) or inherited.

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