The genetic regulation of size variation in the transcriptome of the cerebrum in the chicken and its role in domestication and brain size evolution

BMC Genomics, 2020 · DOI: https://doi.org/10.1186/s12864-020-06908-0 · Published: July 13, 2020

Simple Explanation

This study investigates the genetic factors influencing cerebrum size in chickens, focusing on how domestication has led to a larger cerebrum compared to their wild ancestors. Researchers combined cerebrum size measurements with genome-wide analysis to identify genes and regulatory elements affecting this brain region. The study compares gene expression regulation in the cerebrum with that of the hypothalamus and liver to understand similarities and differences in genetic control across different tissues. The findings suggest that genetic regulation of gene expression in the cerebrum is relatively independent from the hypothalamus, indicating functional rather than developmental coevolution between these brain regions.

Study Duration

Not specified

Participants

59 (26 females and 33 males) F8 individuals

Evidence Level

Not specified

Key Findings

1
One candidate gene, MTF2, was identified as potentially regulating cerebrum size, and it has previous links to brain development.
2
A large number of eQTL were found to regulate the transcriptome in cerebrum tissue, with most acting in trans.
3
The genetic regulation of gene expression in the cerebrum differs significantly from that in the hypothalamus, with fewer shared eQTL, but has more in common with liver tissue.

Research Summary

This study aimed to identify the genetic architecture of the cerebrum in chickens and compare gene expression regulation across different brain regions and somatic tissue. The study identified one candidate gene (MTF2) for cerebrum size regulation and found significant differences in gene expression regulation between the cerebrum and hypothalamus. The findings suggest that genetic regulation of gene expression is relatively independent between brain regions, which has implications for brain size evolution theories.

Practical Implications

Further Investigation of MTF2

MTF2's role in brain development warrants further research to understand its impact on cerebrum size variation across populations.

Rethinking Brain Coevolution

The relative independence of genetic regulation between cerebrum and hypothalamus challenges the idea of strong developmental constraints and supports functional coevolution.

Domestication Insights

The limited overlap of eQTL between multiple tissue types suggests that the neural crest cell hypothesis may not fully explain the genetic basis of domestication traits.

Study Limitations

1
The cerebrum is a large structure with substructures potentially regulated by different genes.
2
eQTL analysis is dependent on the tissue and time-point of sampling.
3
eQTL of small effect may have been missed.

Your Feedback

Was this summary helpful?

Back to Genetics