What is the term for a gene that masks the effect of another gene?

The term for a gene that masks the effect of another gene is a dominant gene. In genetics, the concept of dominance refers to the relationship between alleles, where the dominant allele can overshadow the presence of a recessive allele. When both a dominant and a recessive allele are present in an individual, the phenotype is determined by the dominant allele.

For example, if a gene for flower color has a dominant allele for purple flowers and a recessive allele for white flowers, a plant with at least one dominant allele will exhibit purple flowers, regardless of whether it has one or two recessive alleles. This property of dominant genes is fundamental in inheritance patterns and explains why certain traits can be expressed even when only one copy of the dominant allele is present.

Understanding the role of dominant genes is crucial for predicting inheritance patterns in various organisms and is a cornerstone concept in the study of genetics.