Naturally-Occurring Rare Mutations Cause Mild to Catastrophic Effects in the Multifunctional and Cancer-Associated...

Area of Science:

• Biochemistry and Molecular Biology
• Genetics and Genomics
• Structural Biology

Background:

• The human genome's vast genetic diversity presents challenges in predicting pathogenicity.
• High-throughput pathogenicity prediction remains a significant hurdle in understanding genetic disease implications.

Purpose of the Study:

• To characterize the phenotypic consequences of naturally occurring missense variants on the NQO1 protein.
• To investigate how mutations affect protein stability, function, and structure-function relationships.
• To evaluate the correlation between experimental pathogenicity scores and in silico predictions.

Main Methods:

• Biophysical and structural analyses of eight naturally occurring missense variants in the NQO1 protein.
• Characterization of protein traits including stability and function.
• Generation of experimental pathogenicity scores using 22 characterized NQO1 mutations.
• Comparison of experimental scores with bioinformatic scores from common prediction algorithms.

Main Results:

• Naturally occurring NQO1 mutations exhibit a range of effects, from mild to severe, impacting protein stability and function.
• Some mutations induce functional changes distant from the mutation site, rationalized by mutation nature, location, and local stability.
• Experimental pathogenicity scores show reasonable correlation with bioinformatic predictions, but algorithms struggle with quantitative prediction for individual mutations.

Conclusions:

• Mutational effects can propagate across multifunctional proteins, impacting distant functional sites.
• In silico approaches show promise for genotype-phenotype correlations but require refinement for accurate quantitative prediction.
• Understanding these molecular determinants is crucial for diagnosing loss-of-function genetic diseases.