Re: low mutation rates in flu-viruses
we have no evidence for this. flu has never been isolated from ice
in nature, AFAIK.
When you say: "indefinite time" then there should also be older
viruses around, 100 years or such, but that has never happened before,
AFAIK.
Also the samples from 1918 in permafrost were only small fragments,
hard to reconstruct. And they had to search a lot until they found
a body with some fragments.
maybe frozen droppings or frozen eggs or frozen bird-cadavers ?
Maybe some birds find and eat these frozen eggs, cadavers.
OK for Alaska, but in Hong Kong ??
We have a lot new bird sequences from USA and Alaska recently
shovelers,pintails,mallards, sandpiper
maybe I can make a more complete analysis when ******
stays calm
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Re: low mutation rates in flu-viruses
Question - we know influenza virus can remain viable for an indefinite time in ice, and we are in a period of global warming and ice melts. Is it possible that viral reservoirs are being freed from ice during melts at the same time as possible hosts are around for wider dissemination, re-introducing older viral forms back into the mix?
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Re: low mutation rates in flu-viruses
I want to add this for the evolution of the Alaska avian viruses
filename: swav18m.l6g
Code:18 >A/pintail/Alaska/779/2005(H3N8) 2314 2285 2203 1731 1530 1425 977 851 4:144,109, 99,447, 92,425, 69,273 A/fowl/Rostock/45/1934(H7N1) 2341 2341 2233 1741 1565 1393 1027 890 5:141, 87, 90,494, 91,436, 64,276 A/Ck/Scotland/1959(H5N1) 2341 2341 2233 1767 1565 1458 1027 890 6:152,115, 91,498,116,434, 86,278 A/Bar-h Gs/Qinghai/62/05(H5N1) 2287 2298 2185 1698 1493 1361 982 831 7:144,106, 73,489, 88,503, 65,282 A/tern/South Africa/1961(H5N3) 2341 2341 2233 1779 1565 1454 1027 890 8:142,105, 61,491, 96,500, 57,275 A/duck/Germany/1215/1973(H2N3) 2341 2341 2233 1773 1565 1410 1027 890 9:139, 96, 97,445, 95,483, 61,284 A/turkey/England/1963(H7N3) 2341 2341 2233 1738 1565 1369 1027 890 10: 65, 89,115,435, 75,507, 36, 35 A/turkey/Oregon/1971(H7N3) 2280 2280 2151 1691 1540 1419 1002 855 11: 90,154,111,489, 64,504, 40, 50 A/duck/Memphis/546/1974(H11N9) 2341 2341 493 1760 1565 1460 1027 890 12:142, 88, 78,493, 94,471, 75,281 A/duck/England/1956(H11N6) 2341 2341 2233 1760 1565 1464 1027 890 13:142, 86, 90,380, 90,481, 72,275 A/duck/Czechoslovakia/1956(H4N6) 2341 2341 2233 1738 1565 1426 1027 890 14:140, 90,104,449, 86,516, 62,100 A/Ck/Germany/n/1949(H10N7) 2341 2343 2233 1728 1565 1464 1027 890 15:139, 94,105,451, 97,225, 78,281 A/quail/Italy/1117/1965(H10N8) 2341 2341 2233 1728 1565 1460 1027 890 16:147, 83, 74,147, 93,216, 60,280 A/Dk/UKR/1/1963(H3N8) 2341 2341 2233 1764 1565 1461 1027 890 17:142,103, 65,152, 90,220, 65, 96 A/duck/Chabarovsk/1610/1972(H3N8) 2341 2341 2233 1765 1565 1460 1027 890 19:104,163,141,213,138,218, 58,289 A/equine/New York/1/1983(H3N8) 2299 2302 2192 1723 1519 1425 992 850 21:114,163,147,225,150,230, 64,289 A/swine/Chibi/01/2005/12/15(H3N8) 2341 2341 2233 1762 1565 1460 1027 889 22:164,132,125,202,119,485, 88,283 A/swine/Hong Kong/5190/99(H3N2) 1285 1292 1535 1595 1459 1380 964 838 23:155,125,164,206,172,487,103,274 A/Texas/UR06-0356/2007(H3N2) 2303 2297 2187 1701 1521 1428 988 848 24:149, 88,153,161,157,488, 89,281 A/Russia/WO0200884/72(H3N2) 2341 2341 2233 1765 1565 1466 1027 890 26:144, 83,151,483,145,486, 77,285 A/Index/1957(H2N2) 2314 2317 2209 1730 1520 1447 1002 864 29:140,164,147,484,151,426, 74,279 A/Index/1977(H1N1) 2298 2300 2194 1731 1506 1426 1002 848 34:148,175,157,495,156,431,103,287 A/Kansas/UR06-0068/2007(H1N1) 2283 2303 2197 1741 1506 1423 982 849 36:119,153,141,477,122,420, 57,278 A/Index/early human/1935(H1N1) 2280 2274 2151 1701 1497 1410 982 838 37:114,149,141,477,112,422, 51,275 A/Brevig Mission/1/1918(H1N1) 2280 2274 2151 1701 1497 1410 982 838 38:127,158,140,484,120,422, 64,282 A/Sw/Index/early swine/1935(H1N1) 2280 2274 2151 1701 1497 1410 982 838 43:139,167,161,480,152,431, 79,288 A/swine/Wisconsin/1/1957(H1N1) 2292 2298 2181 1730 1532 1418 995 855 55: 87,122, 49,511,164,423, 85,294 A/Wisconsin/10/98(H1N1) 1600 2341 1494 1064 1512 1458 1027 890 57: 96,131, 66,467,164,429, 89,291 A/******/index/2009-02-01(H1N1) 2280 2274 2151 1701 1497 1410 982 863 64: 87,128, 59,465,161,482, 95,295 A/Swine/Hong Kong/915/2004/10/14(H1N2) 2276 2266 2151 1701 1515 1428 984 861 65: 97,125, 41,468,163,483, 72,293 A/Turkey/MO/24093/99(H1N2) 787 706 729 1701 980 1434 360 846 68: 78,123, 51,201,175,480, 80,291 A/Swine/Nebraska/209/1998(H3N2) 2335 2275 2151 1702 1565 1410 996 847 69: 80,122, 46,200,163,481, 82,293 A/Sw/Index/triple-reassortant/1998(H3N2) 2341 2301 2202 1725 1565 1430 1012 870 71: 81,123, 48,199,163,483, 80,293 A/mallard/SD/Sg-00125/2007/09/19(H3N2) 2334 2335 2226 1763 1557 1444 1017 880 73: 66, 77, 68,479, 57,424, 33, 39 A/turkey/MO/21939/1987(H1N1) 2316 2294 2165 1748 1539 1418 1002 865 74: 60, 56, 83,472, 58,426, 42, 33 A/swine/Saskatchewan/18789/02(H1N1) 2280 2274 2151 1701 1497 1410 982 838 76:---,---,---,478,---,431,---,--- A/Anas crecca/Spain/1384/2007(H1N1) 3 3 3 1701 3 1410 3 3 78:149,109, 79,480,100,430, 61,100 A/duck/Italy/69238/2007(H1N1) 2308 2308 2200 1743 1530 1422 989 887 81:148,103,110,472, 96,432, 65,284 A/swine/Germany/2/1981(H1N1)=1578 2314 2313 2233 1778 1565 1412 1002 864 89:163,129,134,468,119,439,106,311 A/Thailand/271/2005(H1N1) 2301 2193 2120 1778 1541 1452 994 846 90:141, 97, 50,481, 90,349, 69,280 A/shearwater/Australia/1/1973(H6N5) 2341 2341 2233 1744 1564 1454 1027 890 91:142,114, 69,477,103,442, 62, 96 A/duck/Taiwan/0526/72(H6N1) 2341 2340 2233 1744 1563 1458 1027 890 93: 93, 77,134,486, 69,483, 36, 36 A/Turkey/California/189/66(H9N2) 2257 2247 2140 1661 1505 1386 974 831 94: 69, 72,132,486, 71,478, 38,280 A/turkey/Wisconsin/1/1966(H9N2) 2341 2341 2233 1742 1565 1467 1027 890 95: 98,156,129,493, 69,435, 33,279 A/turkey/Ontario/6118/1968(H8N4) 2341 2341 2233 1744 1565 1462 1027 890
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Re: low mutation rates in flu-viruses
now it seems that we can observe the same phenomenon
in North America. More and more sequences are being uploaded
and virus-segments with few differences but decades apart
appear.
I have not yet made a systematic list as above for
HK-Hubei-Henan but e.g.
A/pintail/Alaska/779/2005(H3N8)
seems to have some low-distance relatives from the 70s
or 80s in all segments.
While at the same time being close to other viruses from 2005.
segment 1 : 97.4% similarity for 14 years
segment 2 : 97.5% similarity for 12 years
segment 3 : 95.9% similarity for 26 years
segment 4 : 97.1% similarity for 27 years
segment 5 : 96.6% similarity for 24 years
segment 6 : 96.3% similarity for 28 years
segment 7 : 98.3% similarity for 27 years
segment 8 : 97.4% similarity for 26 years
these are different viruses for the segments, there
was apparantly much reassortment.
---------edit1----------
comparing 52 North American avian viruses from the 70s with
248 North American avian viruses from 2000 or later
Code:1978-2005: 39,29,40,28,28,32,16,15
Code:1977-2004: 29,11,17,81,13,99,14,19
Code:27 years: 29,11,17,28,13,32,14,15
This low-mutation evolution isn't seen in human influenza
and seems to be independent and rarer than "normal"
evolution in birds. But it contributes significantly,
so is the current H5N1 a result of this low mutation evolution
in most segments since the 70s as shown above.
What could it be ? And why isn't it in human flu ?
(but some examples for swine too !)
some possible explanations:
* the virus could persist most of the time in the environment (water ?)
and only some of the time actively replicating in birds
* the virus could persist in some special organs/places inside
some special species of birds (or other animals ?)
* the virus has a method to replicate more reliably with fewer
mutation-rates in some species under certain circumstances
(as seen with influenza-B in humans)
* some gene-configurations are particularly stable and although
the mutation rate isn't lower, only few of them survive due
to selection (including selection for synonymous mutations)
I wish more bird-sequences from the 1970s from EurAsia
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Re: low mutation rates in flu-viruses
compare the differences in PB2 between these 4 viruses:
Code:#differences 1 2 3 4 --------------------------------------------------- 1 >A/duck/England/1956(H11N6) 0 85 103 127 2 >A/Dk/HK/7/1975(H3N2) 85 0 26 56 3 >A/Dk/Zhejiang/11/00(H5N1) 103 26 0 34 4 >A/Dk/Guangxi/35/01(H5N1) 127 56 34 0
they are pretty much "in a line". No room for a lab-error,
the "error" can't know the required mutations.
This would all be not so surprising , if the date-differences
would match the mutations-differences But :
there are 25 years between 2) and 3), with
only 26 differences !!
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Re: low mutation rates in flu-viruses
strange low-mutation-rate in PB2:
Code:0000000000000000000000000000000000000000000011111111111111111111111111111111111111111111111111111111111111111112222222222222222 PB2 0001222223333333444445555666677788888999999900001112222223333334444444555555555566666677777777777888888999999990000000000111222 4555557780001359047792289566612316788022348902494470247890112780566789113455678924445502234455667345678026778891233445799124128 6576250953695943271752887403671805925014621080153736455706176164514321251947924361246972810605149921081599176982814694948842866 -codon-position----------------------------11 1 1 1 1 11 1 1 1 2 2 1 1 ---Index-----------------------------------TCATGGATGTCAAGCTAACCTGTGAGGCCGTGTCCCCGTATGGACACACCTATATCAAGCACTGAGGGGTTGTCGCTCTGAGACGAGTCCACAGAGATTGTGGGTCCGCCCCCCATACCGCAGAGGG A/Dk/Hongkong/7/1975(H3N2) ............................................................................................................................... A/Dk/Nanchang/1681/1992(H3N8) .......C.....A.CG.TGCA.AG....A..CT...A.G.......GTTCGAGC........A..A.A....A.......AG...A.T.GTG....C....AAC......T..GA..T....G... A/Dk/Zhejiang/11/00(H5N1) ....A.............T....A........C.T....G.A......T....GC.......C..AAA...A......C..A......T.GT......C..........T..TT.....A......A A/black Dk/Western AUS/4954/1983(H3N8) ....AA..AA...AT.......CA.AATG.CA...TT.C.G.A...T.TT.....TGCA.GT..G..A..C.C.ATCT.A...AAG.C.T.T.AGA..C.......AAT.......GG.ATGA.... A/slaty-backed gull/Shandong/38/04(H5N1) CTGC..G.A.TGG....GT....A.A.TT..A.T......A..GTG..T..........A.T.......C..........G..........T..G.G..ACA.A.T....T.....G.....A.AA.
Code:0000000000111111111111222 2234667889122344677789001 5837563162447767424640492 2591438054755143180125944 -codon-position---------------------------- 1 1 Index--------------------------------------GGGCGCGTCACATCGGGCAATGAGG A/Dk/HK/7/1975(H3N2) ......................... A/Dk/Nanchang/1681/1992(H3N8) ..AT...CTGTGC.A.ATG..A... A/Dk/Zhejiang/11/00(H5N1) A..T...C.G.GC.AAATG.C..A. A/black Dk/Western AUS/4954/1983(H3N8) AAA.ATA...T..T.A...GC.GAA A/slaty-backed gull/Shandong/38/04(H5N1) .A.TATA.T....T.....G.AG.A
Code:#differences in PB2 1 2 3 4 5 6 7 --------------------------------------------------------------------- 1 >A/Dk/HK/7/1975(H3N2) 0, 43, 56, 94, 39, 98, 26 2 >A/Dk/Nanchang/1681/92(H3N8) 43, 0, 89,115, 70,119, 45 3 >A/black Dk/W.AUS/4954/83(H3N8) 56, 89, 0,111, 71,132, 68 4 >A/Ck/Scotland/1959(H5N1) 94,115,111, 0,113,168,108 5 >A/slaty-backed gull/SD/38/04(H5N1) 39, 70, 71,113, 0,125, 57 6 >A/Bar-h Gs/Qinghai/62/05(H5N1) 98,119,132,168,125, 0, 78 7 >A/Dk/Zhejiang/11/00(H5N1) 26, 45, 68,108, 57, 78, 0
is already so low, that Qinghai might be a direct descendant of 1959.
But some of the other differences are even much lower, so that
we should assume either errors or slow evolution, which is unusual.
The HK/75 virus had already given some examples of slow evolution
above in this thread
But it's not just this one virus. Close to HK75 in PB2 are e.g.
A/Dk/HK/24/76(H4N2)
A/Dk/HK/562/79(H10N9)
A/Dk/HK/312/78(H5N3)
A/Dk/Nanchang/1681/92(H3N8)
A/black Dk/AUS/751/78(H3N8)
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Re: low mutation rates in flu-viruses
a good example is also
A/Guangxi/50/2005(H5N1) {gx50} which has only 49 differences
in 3 years to A/Henan/16/2004.
gx50 can be viewn as the best matching anchestor-virus to current
H5N1 in most segments.
These slow evolutions with few mutations are rare and not seen
in human flu AFAIK with the exception of 1977 H1N1.
In the Qinghai strain we have one (and only one) other such example :
the Hungary-Suffolk virus. It suggests an abiotic reservoir,
or some place inside the bodies, where the virus can survive for
some time without mutating/replication.
Could this be the key why the virus is so successful in
SE-Asia ? What could be the reservoir where the virus
survives without mutating ? Why is this obviously useful
feature so rare in influenza ?
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Re: low mutation rates in flu-viruses
minimum distance in 0/00 to groups :
Code:19 times HK 1970s 059,077,092,097,047,393,025,057, 37.Ck/Germany/n/1949(H10N7) 099,093,091,369,068,393,044,053, 38.fowl/Dobson/1927(H7N7) 064,080,055,088,034,392,026,031, 40.Dk/UKR/1/1963(H3N8) 040,081,071,082,040,071,031,025, 41.Ck/Scotland/1959(H5N1) 046,082,066,093,074,123,054,050, 42.human/China/GD02/06(H5N1) 042,076,079,090,074,114,058,051, 43.Bar-h Gs/Qinghai/62/05(H5N1) 138,160,133,348,126,133,082,097, 44.Sw/1931(H1N1) 134,151,129,343,114,129,068,059, 45.Brevig Mission/1/1918(H1N1) 143,162,136,342,130,164,093,087, 46.Alaska/1935(H1N1) 148,161,136,345,141,169,084,086, 47.Hickox/1940(H1N1) 166,175,148,351,154,199,112,115, 48.Kansas/UR06-0068/2007(H1N1) 150,074,144,081,146,069,093,087, 49.Japan/305/57(H2N2) 153,085,145,062,154,096,096,104, 50.Russia/WO0200884/72(H3N2) 158,117,158,148,169,149,111,124, 51.Texas/UR06-0356/2007(H3N2) 6 times Hubei 1997 067,082,102,470,064,461,024,267, 37.Ck/Germany/n/1949(H10N7) 103,100,101,466,072,466,048,058, 38.fowl/Dobson/1927(H7N7) 064,084,066,473,061,397,024,035, 40.Dk/UKR/1/1963(H3N8) 065,087,086,120,055,114,030,030, 41.Ck/Scotland/1959(H5N1) 054,074,070,038,064,043,017,052, 42.human/China/GD02/06(H5N1) 049,065,061,037,065,019,015,051, 43.Bar-h Gs/Qinghai/62/05(H5N1) 140,159,138,350,130,154,082,096, 44.Sw/1931(H1N1) 135,151,133,349,119,168,066,060, 45.Brevig Mission/1/1918(H1N1) 147,162,140,362,134,187,093,091, 46.Alaska/1935(H1N1) 153,158,141,364,142,197,086,087, 47.Hickox/1940(H1N1) 170,175,152,370,153,213,115,117, 48.Kansas/UR06-0068/2007(H1N1) 154,081,148,301,148,495,095,092, 49.Japan/305/57(H2N2) 160,090,144,483,157,473,098,106, 50.Russia/WO0200884/72(H3N2) 162,122,160,490,170,482,114,124, 51.Texas/UR06-0356/2007(H3N2) 11 times Henan 2004 071,082,107,476,065,488,029,269, 37.Ck/Germany/n/1949(H10N7) 105,103,102,466,074,491,052,053, 38.fowl/Dobson/1927(H7N7) 064,086,066,480,064,398,029,036, 40.Dk/UKR/1/1963(H3N8) 061,089,089,126,057,124,035,027, 41.Ck/Scotland/1959(H5N1) 021,022,061,025,009,033,007,018, 42.human/China/GD02/06(H5N1) 018,016,016,022,012,011,009,019, 43.Bar-h Gs/Qinghai/62/05(H5N1) 146,160,139,352,133,168,087,096, 44.Sw/1931(H1N1) 141,151,136,352,117,171,069,057, 45.Brevig Mission/1/1918(H1N1) 152,162,143,367,133,190,096,090, 46.Alaska/1935(H1N1) 157,162,139,363,140,199,089,085, 47.Hickox/1940(H1N1) 171,176,151,370,151,216,116,109, 48.Kansas/UR06-0068/2007(H1N1) 158,079,148,302,146,492,099,090, 49.Japan/305/57(H2N2) 161,092,146,485,159,481,103,112, 50.Russia/WO0200884/72(H3N2) 164,125,159,494,170,490,117,129, 51.Texas/UR06-0356/2007(H3N2) 032,011,016,080,013,120,013,014, HK-Henan 010,003,016,020,003,029,005,008, Hubei-Henan 034,011,017,072,014,095,008,012, HK - Hubei
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Re: low mutation rates in flu-viruses
Originally posted by Vibrant62 View PostThere is another theory that could explain the phenomenom.
We know that viri held in deep freeze in artic and antarctic ice are still - sometimes - viable when released from deep freeze.
It is entirely possible that birds or other vectors have transported viruses to areas where subzero temperatures predominate, and that, with global warming and ice melts such viruses are released again into the environment.
Thus a virus from 1978 (or prior) could have become locked in ice, and then become released as warming has resulted in ice melts with a subsequent exposure to a viable host, restarting the cycle.
To test such a theory, where exactly were viral samples that matched earlier (unchanged) samples identified? Was it in a cold temperature area? Could it explain what has been seen in genetic sequence samples?
Just to add to the mix...
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Re: low mutation rates in flu-viruses
Originally posted by cartski View PostI'm sorry, but I need much more rudimentary statements about what the science is in order to follow your experiment.
What's the original thread about this? Statements from Vallat about the "stability" of the H5N1 virus?
And you're saying that the rate of genetic change in the Quingai virus is very low, and therefore supports Vallat's statements?
J.
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Re: low mutation rates in flu-viruses
I assume human flu evolves with about 35 nucleotide-changes
per year per genome and avian flu with about 45.
After many years, some mutations will undo previous mutations
instead of forming new ones, so the distance between
2 strains grows more slowly and after about 200 years
remains almost constant.
total differences for the 8 segments:
9 >A/Brevig Mission/1/1918(H1N1)
----------------------------------------------
1:313,357,282,784,178,678, 68,239, 1949(H10N7)
2:318,372,269,818,191,688, 72, 38, 1927(H7N7)
3:317, 0,263,522,193, 0, 68, 37, 1902(H7N7) [I don't trust this sequence, maybe incorrect]
4:330,344,279,792,179,567, 68, 54, 1963(H3N8)
5:321,358,273,572,189,164, 72, 49, 1959(H5N1)
6:358,353,291,574,207,241, 95, 73, 2006(H5N1)
7:349,361,300,589,204,235, 93, 73, 2005(H5N1)
8:101,105,110,112, 66, 72, 39, 38, 1931(H1N1)
9: 0, 0, 0, 0, 0, 0, 0, 0, 1918(H1N1)
10:115, 87, 97,141, 74, 96, 40, 33, 1935(H1N1)
11:140,118,125,178, 86,112, 37, 36, 1940(H1N1)
12:240,211,196,262,133,196, 73, 75, 2007(H1N1)
13:167,359,136,583,113,707, 45, 48, 1957(H2N2)
14:222,365,174,803,133,696, 59, 69, 1972(H3N2)
15:270,403,239,806,188,691, 81, 95, 2007(H3N2)
differences in 1/10 percent:
9 >A/Brevig Mission/1/1918(H1N1)
1:137,156,131,477,118,489, 69,284,
2:139,163,125,494,127,496, 73, 45,
3:138, 0,122,549,128, 0, 69, 44,
4:144,151,129,475,119,410, 69, 64,
5:140,157,126,338,126,116, 73, 58,
6:156,155,135,339,138,178, 96, 88,
7:153,158,139,350,136,173, 94, 88,
8: 44, 46, 51, 65, 44, 51, 39, 45,
9: 0, 0, 0, 0, 0, 0, 0, 0,
10: 50, 38, 45, 82, 49, 70, 40, 39,
11: 61, 51, 58,104, 57, 79, 37, 42,
12:105, 92, 91,154, 88,138, 74, 89,
13: 73,157, 63,345, 75,511, 45, 57,
14: 97,160, 80,481, 88,503, 60, 82,
15:118,177,111,483,125,499, 82,113,
12:240,211,196,262,133,196, 73, 75, 2007(H1N1)
1386 changes in 89 years (~25 of these inactive) = 22 mutations per year
11:140,118,125,178, 86,112, 37, 36, 1940(H1N1)
832 differences in 22 years = 38 mutations per year
10:115, 87, 97,141, 74, 96, 40, 33, 1935(H1N1)
683 differences in 17 years = 40 mutations per year
14 >A/Russia/WO0200884/72(H3N2) - 15 >A/Texas/UR06-0356/2007(H3N2)
122,150,121,196, 98,130, 41, 45
903 differences in 35 years = 26 mutations per year
Qinghai H5N1 got its PB2 almost directly from A/Ck/Scotland/1959(H5N1).
Also probably M,NS and maybe HA,NP,NA :
73,117,111,131, 89,129, 64, 67 differences in 0/00 , 46 years
while PB1 is from 1957 panflu and PA from the 1963 Ukraine duck. Or similar/related viruses.Last edited by gsgs; May 20, 2008, 02:35 PM.
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Re: low mutation rates in flu-viruses
stasis
Taubenberger et.al 2002 refer to :
Webster, R. G., G. B. Sharp, and E. C. Claas. 1995. Interspecies transmission of influenza viruses. Am. J. Respir. Crit. Care Med. 152:S25-30.
http://cat.inist.fr/?aModele=a...
> In contrast to the rapid, progressive changes in both the
> nucleotide and amino acid sequences of
> mammalian virus gene lineages, avian virus genes show far less
> variation and, in most cases, appear to be in evolutionary stasis
is this true ? I can't verify this. It's not, what we see with H5N1.
(nor H9N2,H7N?,...)
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Re: low mutation rates in flu-viruses
usual enumeration : (1,2,3,4,5,6,7,8) = (PB2,PB1,PA,HA,NP,NA,M,NS)
I should add, that these low rates are often only in one or few segments
and only in one or few members from the groups, while the others
have more mutations. Want the whole table ?
OK, I uploaded it here:
numbers are differences in 1/100 percent for the 8 segments, 44 viruses
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Re: low mutation rates in flu-viruses
Originally posted by gsgs View PostI looked at 3 groups of viruses:
"2004": 11 H5N1- viruses from Henan,2004
"1997": 6 H5N1 - viruses from Hubei,1997
"1977": 19 avian viruses from Hongkong, 1975-1979
the minimum distance between the groups in the 8 segements is:
Code:1977-1997: 346,119,183,735,146,1069,097,123 1997-2004: 100,030,079,191,033,0143,038,089 1977-2004: 290,114,167,810,133,1080,136,191
This is very low.
1977-1997: 346,119,183,735 (Na?),146,1069 (Ha?) ,097,123
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Re: low mutation rates in flu-viruses
not much ice in Hongkong,Hubei,Henan.
Also, the low mutation was 1977-1997 as well as 1997-2004,
and in several segments so it would have to involve multiple
freezing events and reassortments.
Another H5N1-low-mutation-example was
HK/1997-Vietnam/2005.
No such low mutation rates are found in the Qinghai strain
(except the Hungary-Suffolk virus)
which is at home in the west Sibirian wetlands with first freezing
as early as July in the nothern areas.
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