GC content shift

GC content shift is an evolutionary genome-wide change in the GC content of an organism. The evolutionary consequences of such a change is unknown. They are detected by comparing the genomes of two related organisms that share a recent common ancestor, and determining if their have different:

• AT/GC genomic composition
• High rate of synonymous mutations for syntenic gene pairs
• Amino acid usage frequencies
• Codon usage frequencies

Comparison of Schizosaccharomyces fungi japonicus strain yFS275 and pombe 972h-

SynMap syntenic dotplot of two Schizosaccharomyces fungi: japonicus strain yFS275 (x-axis) and pombe 972h (y-axis). Syntenic gene pairs are colored based on their synonymous mutation rates. While there have been many genomic rearrangements since these lineages diverged, nearly every genomic regions in both species have a syntenic partner region (albeit it small regions of contiguous synteny). Results may be regenerated at: http://genomevolution.org/r/pi4

GEvo analysis of syntenic regions from the Schizosaccharomyces fungi japonicus strain yFS275 (top) and pombe 972h- (bottom). Gene models are colored based on the percent GC content of GC3. Red is AT rich; green GC rich; yellow 50/50 AT/GC. Results may be regenerated at: http://genomevolution.org/r/pi7