Locus heterogeneity is best defined as?

Locus heterogeneity refers to the phenomenon where mutations in different genes can lead to the same disorder. This means that more than one genetic locus is responsible for the phenotype associated with a particular condition. In other words, individuals with the same condition might have disease-causing variants in distinct genes, demonstrating that the genetic basis of a single disease can be complex and varied.

This concept is particularly important in genetic counseling, as it guides the interpretation of genetic testing results and helps in understanding the inheritance patterns of certain disorders. For instance, a patient diagnosed with a specific genetic condition may carry mutations in several different genes, resulting in similar clinical features despite the underlying genetic variations. This illustrates how locus heterogeneity contributes to the complexity of genetic diseases and reinforces the idea that a thorough evaluation is often necessary in genetic assessments.