Test Freyja Update function

[hoelzer]

Freyja was recently added and also has a update parameter. To test this new functionality, we can run poreCov with a sample that has a very recent lineage assignment which is not part of the Freyja version in the container (from March I think):

Recent designations:

https://github.com/cov-lineages/pango-designation/releases/tag/v1.27

We have a Run24-123 (17.05.2024) with samples

IMSSC2-174-2024-00065 - assigned JN 1.48.1 (designated 15.04.2024) IMSSC2-99-2024-00026 - assigned JN 1.16.2 (designated 15.04.2024) IMSSC2-63-2024-00057 - assigned KP 2.3 (designated 15.04.2024)

The data is on the HPC here:

<usual-path>/2024-05-17/*Run24-123/

[hoelzer]

In this context, the help mssg

--screen_reads           Determines the Pangolineage of each individual read (takes time, needs --freyja and/or --lcs)

Is wrong. I am not 100% sure how LCS was doing this, but Freyja is not giving a lineage assignment for each read. Freyja is doing a deconvolution of the variant calls to estimate the proportion of lineages.

In this context, I am also wondering @DataSpott @replikation if we could not remove the screen_reads parameter?

Then, the user can just activate freyja or LCS with the parameter that is anyway available?

[hoelzer]

Alright, I tested this on patient samples.

here is the plot w/o freyja_update which then uses a Freyja database that is part of the container (from March 2024 or so)

here is the same data and command but with freyja_update and we can see that the update function does something (attention, the sample columns are not exactly the same)

Let's check the "interesting" samples (if I can see the colors correctly)

IMSSC2-174-2024-00065, barcode13 - assigned JN 1.48.1 (designated 15.04.2024)

• w/o freyja update: JN.1.16.1
• w/ freyja update: 50% JN 1.16.1 and 50% JN1.48.1

IMSSC2-99-2024-00026, barcode 12 - assigned JN 1.16.2 (designated 15.04.2024)

• w/o freyja update: JN.1.16
• w/ freyja update: 80% JN.1.16.2 and 20% JN.1.16

IMSSC2-63-2024-00057, barcode 18 - assigned KP 2.3 (designated 15.04.2024)

• w/o freyja update: KP.2
• w/ freyja update: KP.2.3

Summary

This works very well! And the update function also does it's job. Still, I think we should implement a more robust way where the used freyja reference db is also versionized and stored. But this can be done in another issue/PR.

[replikation]

In this context, the help mssg

--screen_reads           Determines the Pangolineage of each individual read (takes time, needs --freyja and/or --lcs)

Is wrong. I am not 100% sure how LCS was doing this, but Freyja is not giving a lineage assignment for each read. Freyja is doing a deconvolution of the variant calls to estimate the proportion of lineages.

In this context, I am also wondering @DataSpott @replikation if we could not remove the screen_reads parameter?

Then, the user can just activate freyja or LCS with the parameter that is anyway available?

agree on this screen_reads part to simplify. but i prefer descriptions rather than tool names. (e.g. --screen_reads Uses freya to.....) maybe deprecate LCS?

[Krannich479]

Amazing results @hoelzer !

[hoelzer]

In this context, the help mssg

--screen_reads           Determines the Pangolineage of each individual read (takes time, needs --freyja and/or --lcs)

Is wrong. I am not 100% sure how LCS was doing this, but Freyja is not giving a lineage assignment for each read. Freyja is doing a deconvolution of the variant calls to estimate the proportion of lineages. In this context, I am also wondering @DataSpott @replikation if we could not remove the screen_reads parameter? Then, the user can just activate freyja or LCS with the parameter that is anyway available?

agree on this screen_reads part to simplify. but i prefer descriptions rather than tool names. (e.g. --screen_reads Uses freya to.....) maybe deprecate LCA?

From my pov we could discontinue LCS. And then screen_reads would simply activate freyja.

@Krannich479 @MarieLataretu are you using LCS for anything? From my pov it's not well-updated and freyja would be anyway preferable

[MarieLataretu]

@Krannich479 @MarieLataretu are you using LCS for anything? From my pov it's not well-updated and freyja would be anyway preferable

We occasionally investigate the LCS results in special cases. But I agree that LCS is not up-to-date (even if we could update it)!

Maybe deprecation is a nice compromise? @replikation , it would be usable/available for some time, right?

[replikation]

yep

[MarieLataretu]

I'd vote for deprecating LCS, then. If we need LCS results in the near future for whatever reason, we'd still have the option to run it easily

[hoelzer]

Agree!

[Krannich479]

Regarding your freja results, do you mind re-running freja if I error-correct you the read pools with herro? This insight would bolster my (dis-)trust in EC for variant calling.

[hoelzer]

@Krannich479 pleasure.

We could also then do a re-basecalling of the run with v5 Dorado SUP and see any differences.