A quite recent Japanese Sub-lineage of KP.3.3* with S:A435S (G22865T) and other mutations, 8 seqs

[krosa1910]

I found this when looking at KP.3.3* type lineages and it seems to be pretty abundant in Japan now

Evolutionary Path: A8576G(Orf1a:K2771E) [which is somehow a random mutation not showing beneficity but seemingly popular in KP.3.3* population] -> T23677C->G25440T(Orf3:K16N)->G22865T(S:A435S),C29095T (current lineage)
Gisaid Search: T23677C,C29095T,C25006T
Earliest Sequence: EPI_ISL_19686931 Japan 2024-12-02
Latest Sequence: EPI_ISL_19681126 Japan 2025-01-13
Geographic Distribution: 8 ,All Japan, but seems to be located in multiple region(prefecture)

https://nextstrain.org/fetch/genome.ucsc.edu/trash/hgPhyloPlace/singleSubtreeAuspice_genome_2625f6_8a8060.json?f_userOrOld=uploaded%20sample&label=id:node_2515561 (Under Gisaid Search: T23677C,C25006T,C28291A)

https://nextstrain.org/fetch/genome.ucsc.edu/trash/hgPhyloPlace/singleSubtreeAuspice_genome_3efd09_8aa4f0.json?f_userOrOld=uploaded%20sample&label=id:node_5771858

S:A435S has appeared in KP.3.3.2* and MC.10.1.1*, both being mildly successful, so I would like to see how it behave in this KP.3.3* sublineage.

Japan has only collected 155 seqs in 2025 and 4 are these and distributed in two prefectures, so it possibly has some level of circulation there.

[FedeGueli]

good catch thanks