Question

What factors of a structural gene can affect the inheritance of a trait?

Answer 1

Structural genes: These are the genes that are responsible for the synthesis of a functional protein product.

The following factors are responsible for the inheritance of a trait encoded by a structural gene:

1. If a pedigree appears to skip a generation, consider incomplete penetrance, incomplete expression, and (less likely) genomic imprinting.
2. Gene expression can also be modified by sex-limited inheritance, genomic imprinting, codominance of alleles, and X chromosome inactivation
3. Penetrance is defined as the expression of a gene.
4. It is defined as the percentage of people who have the gene and who develop the corresponding phenotype.
5. A gene with incomplete (low) penetrance may not be expressed even when the trait is dominant or when it is recessive.
6. Genomic imprinting is the differential expression of genetic material depending on whether it has been inherited from the father or mother.
7. A trait that appears in only one sex is called sex-limited.
8. Sex-limited inheritance is distinct from X-linked inheritance, which refers to traits carried on the X chromosome.
9. Sex-limited inheritance refers to special cases in which sex hormones and other physiologic differences between males and females alter the expressivity and penetrance of a gene.