wyp1125 / MCScanX

MCScanX: Multiple Collinearity Scan toolkit X version. The most popular synteny analysis tool in the world!
http://chibba.pgml.uga.edu/mcscan2/
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Low number of collinear genes #68

Open DustinSokolowski opened 1 year ago

DustinSokolowski commented 1 year ago

Hey!

Thank you for the excellent tool. I am attempting to identify syntenic blocks and tandem duplications between the mouse (mm10) and naked mole-rat genome that I assembled and I am finding some surprisingly low collinearity.

When using the parameters on the github page, I found 26.8% gene collinearity, which I thought was fairly low.

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Here are a handful of chromosomes (with X as a highly syntenic reference)

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I was hoping to look at a linear plot (or dot plot) of some tandem duplicated genes, but a lot of the genes didn't exist.

One is a cytochrome P450 gene(s), which in the blastp file has a very strong set of very consistent hits (all other CYP genes), see below. Strangely, these hits did not make it into the collinearity file.

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My initial guess was that the BLAST hits were other CYP genes on other chromosomes and therefore couldn't chain the regions together, so I allowed for up to 15 hits in blastp. Once completed, I ended up with a slightly lower collinearity overall, which I'm not sure how to interpret.

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Have you come across this type of issue before and do you have any suggestions?

Best, Dustin