Old genes experience stronger translational selection than young genes

Area of Science:

• Evolutionary biology
• Genomics
• Molecular biology

Background:

• Synonymous codon usage selection influences translation efficiency and accuracy across organisms.
• The relationship between translational selection and gene age remains largely unexplored.

Purpose of the Study:

• To investigate the correlation between gene age and the strength of translational selection in human genes.
• To analyze how translational selection differs between gene duplicates and singletons, and between housekeeping and tissue-specific genes.

Main Methods:

• Comparative analysis of translational selection strength across genes of varying evolutionary ages in the human genome.
• Examination of translational selection patterns in gene duplicates versus singletons.
• Assessment of translational selection in housekeeping versus tissue-specific genes.

Main Results:

• Older human genes display significantly stronger translational selection compared to younger genes.
• Translational selection acts similarly on old singletons and duplicates, primarily driven by housekeeping genes.
• Young singletons show stronger translational selection than young duplicates, potentially due to functional redundancy in duplicates.

Conclusions:

• Translational selection is not constant throughout a gene's evolutionary lifespan but is closely associated with gene age.
• Gene age is a critical factor influencing the strength and pattern of translational selection.