Rhiza Labs FluTracker Forum

Receptor binding domain changes are appearing at increasing frequency. One position (225) has changed at least three times (D225G, D225N and D225E). There is speculation that Ukraine sequences also contain receptor binding domain changes.

These genbank sequences have D225G

gb|GU189649.1| Influenza A virus (A/Zhejiang/DTID-ZJU03/2009(... 34.2 3.0
gb|GU112090.1| Influenza A virus (A/Zhejiang/DTID-ZJU02/2009(... 34.2 3.0
gb|GU108486.1| Influenza A virus (A/Zhejiang-Yiwu/11/2009(H1N... 34.2 3.0
gb|CY047074.1| Influenza A virus (A/Catalonia/NS1706/2009(H1N... 34.2 3.0
gb|GU014750.1| Influenza A virus (A/Hiroshima/201/2009(H1N1))... 34.2 3.0
gb|GQ915018.1| Influenza A virus (A/Sao Paulo/53225/2009(H1N1... 34.2 3.0
gb|GQ915017.1| Influenza A virus (A/Sao Paulo/53206/2009(H1N1... 34.2 3.0
gb|GQ457487.1| Influenza A virus (A/Texas/05/2009(H1N1)) segm... 34.2 3.0
gb|GQ379822.1| Influenza A virus (A/Mexico/InDRE4114/2009(H1N... 34.2 3.0
gb|GQ374893.1| Influenza A virus (A/reassortant/IDCDC-RG18(Te... 34.2 3.0
gb|GQ280121.1| Influenza A virus (A/reassortant/NIBRG-121(Cal... 34.2 3.0
gb|GQ232076.1| Influenza A virus (A/Texas/11/2009(H1N1)) segm... 34.2 3.0
gb|GQ200237.1| Influenza A virus (A/Georgia/01/2009(H1N1)) se... 34.2 3.0
gb|GQ162194.1| Influenza A virus (A/Mexico/3955/2009(H1N1)) s... 34.2 3.0
gb|GQ160568.1| Influenza A virus (A/New York/04/2009(H1N1)) s... 34.2 3.0
gb|GQ132145.1| Influenza A virus (A/Mexico/InDRE4114/2009(H1N... 34.2 3.0

The Zheijiang sequences are associated with the first severe case in the province (on Sept 6). He recovered after speding several weeks in the hospital. All three isolates were from Yiwa.

Both Sao Paulo cases had fatal lung infections (collected in July and August).

Texas cases were from April 9M and 16M, which were likely milder.

What is the (possible) significance of these changes?

Dr Niman, Could you explain to us laypeople, what the 225 means exactly so that we understand, when you have time. Thank you

Much of the baclground on positions 193 and 225 are discussed here

http://precedings.nature.com/documents/2832/version/1

A193T was key in establishing H274Y in seasonal H1N1

S193F and D225N were key in establishing S31N in seasonal H3N2.

The Zheijiang sequence has three other newly acquired polymorphisms, all of which are on Hangzhou/1 as seen in the three travel logs below

gb|GU189649.1| Influenza A virus (A/Zhejiang/DTID-ZJU03/2009(... 34.2 3.0
gb|GU112090.1| Influenza A virus (A/Zhejiang/DTID-ZJU02/2009(... 34.2 3.0
gb|GU108486.1| Influenza A virus (A/Zhejiang-Yiwu/11/2009(H1N... 34.2 3.0
gb|CY047712.1| Influenza A virus (A/Hangzhou/1/2009(H1N1)) se... 34.2 3.0

******************************
gb|GU189649.1| Influenza A virus (A/Zhejiang/DTID-ZJU03/2009(... 38.2 0.19
gb|GU112090.1| Influenza A virus (A/Zhejiang/DTID-ZJU02/2009(... 38.2 0.19
gb|GU108486.1| Influenza A virus (A/Zhejiang-Yiwu/11/2009(H1N... 38.2 0.19
gb|CY047712.1| Influenza A virus (A/Hangzhou/1/2009(H1N1)) se... 38.2 0.19
gb|CY040594.1| Influenza A virus (A/swine/North Carolina/4511... 38.2 0.19

*******************************
gb|GU189649.1| Influenza A virus (A/Zhejiang/DTID-ZJU03/2009(... 42.1 0.018
gb|GU112090.1| Influenza A virus (A/Zhejiang/DTID-ZJU02/2009(... 42.1 0.018
gb|GU108486.1| Influenza A virus (A/Zhejiang-Yiwu/11/2009(H1N... 42.1 0.018
gb|CY047712.1| Influenza A virus (A/Hangzhou/1/2009(H1N1)) se... 42.1 0.018

Two of the travel logs for the Sydney isolate

gb|CY049691.1| Influenza A virus (A/Singapore/GP2711/2009(H1N... 32.2 12
gb|CY047150.1| Influenza A virus (A/Catalonia/S1138/2009(H1N1... 32.2 12
gb|GU014748.1| Influenza A virus (A/Gifu-C/67/2009(H1N1)) seg... 32.2 12
gb|GQ377064.1| Influenza A virus (A/Virginia/05/2009(H1N1)) s... 32.2 12
gb|GQ232009.1| Influenza A virus (A/Kentucky/05/2009(H1N1)) s... 32.2 12

************************

gb|CY049691.1| Influenza A virus (A/Singapore/GP2711/2009(H1N... 38.2 0.19
gb|GU014748.1| Influenza A virus (A/Gifu-C/67/2009(H1N1)) seg... 38.2 0.19

Map of Yiwu
http://flutracker.rhizalabs.com/flu/gma ... 375&zoom=7

The sharing of three polymorphisms with the Hangzhou isolates, which does not have D225G, indicates that D225G was acquired by recombination and is "in play".