Identification of a Heritable Polymorphism in Bovine PRNP Associated with Genetic Transmissible Spongiform Encephalopathy: Evidence of Heritable BSE
Eric M. Nicholson1#*, Brian W. Brunelle2#, Juergen A. Richt1, Marcus E. Kehrli, Jr1, Justin J. Greenlee1
1 Virus and Prion Diseases of Livestock Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, Iowa, United States of America2 Pre-Harvest Food Safety and Enteric Diseases Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, Iowa, United States of America
Abstract Background Bovine spongiform encephalopathy (BSE) is a transmissible spongiform encephalopathy (TSE) of cattle. Classical BSE is associated with ingestion of BSE-contaminated feedstuffs. H- and L-type BSE, collectively known as atypical BSE, differ from classical BSE by displaying a different disease phenotype and they have not been linked to the consumption of contaminated feed. Interestingly, the 2006 US H-type atypical BSE animal had a polymorphism at codon 211 of the bovine prion gene resulting in a glutamic acid to lysine substitution (E211K). This substitution is analogous a human polymorphism associated with the most prevalent form of heritable TSE in humans, and it is considered to have caused BSE in the 2006 US atypical BSE animal. In order to determine if this amino acid change is a heritable trait in cattle, we sequenced the prion alleles of the only known offspring of this animal, a 2-year-old heifer.
Principal Findings Sequence analysis revealed that both the 2006 US atypical BSE animal and its 2-year-old heifer were heterozygous at bovine prion gene nucleotides 631 through 633 for GAA (glutamic acid) and AAA (lysine). Both animals carry the E211K polymorphism, indicating that the allele is heritable and may persist within the cattle population.
Conclusions This is the first evidence that the E211K polymorphism is a germline polymorphism, not a somatic mutation, suggesting BSE may be transmitted genetically in cattle. In the event that E211K proves to result in a genetic form of BSE, this would be the first indication that all 3 etiologic forms of TSEs (spontaneous, hereditary, and infectious) are present in a non-human species. Atypical BSE arising as both genetic and spontaneous disease, in the context of reports that at least some forms of atypical BSE can convert to classical BSE in mice, suggests a cattle origin for classical BSE.
snip...
Discussion Few genetic polymorphisms within the bovine PRNP coding region result in an amino acid change [15], and only these two related animals encode for an amino acid substitution analogous to any polymorphism associated with an inherited TSE. While rare, the fact that the substitution is heritable clearly indicates that this allele may be present in the cattle population at some, albeit low, frequency.
Etiology of TSEs is complex with human TSEs known to occur as infectious, spontaneous, and genetic diseases. While transmission through peripheral exposure to infectious material is clearly involved in the feedborne, classical BSE epizootic, the origin of BSE is unresolved. Although sheep scrapie has been suggested as a potential source of BSE [18], scrapie has yet to be transmitted to cattle orally [19]. This discrepancy necessitates a reevaluation of the source of the BSE epizootic. Single amino acid substitutions made within mouse PrP analogous to those associated with human genetic TSEs were found to cause comparable disease in transgenic mice [20]–[22]. Thus, the identification of the E211K polymorphism in cattle has important implications. Here we report a germline polymorphism present in cattle analogous to a polymorphism in humans that results in a genetic TSE with complete penetrance.
The fact that the 2-year-old heifer has not developed clinical signs associated with BSE is consistent with the late onset of hereditary human TSEs [23] and atypical BSE [24]. Consistent with these observations, the 2006 US atypical BSE animal that contained the E211K variant was estimated to be 10 years of age at onset of clinical signs [16]. The heifer will be used to generate experimental animals containing the E211K polymorphism for studies that will establish if the polymorphism influences TSE susceptibility in cattle and if the E211K polymorphism results in genetic BSE. Recently, it has been suggested that the atypical BSE cases that lack amino acid changes in the prion protein are likely spontaneous TSEs of cattle akin to spontaneous TSEs in humans [6], [24]–[26]. The presence of the E211K polymorphism in an atypical BSE positive animal, however, indicates a potential genetic etiology of cattle TSEs much like inherited TSEs in humans. This preliminary evidence of a genetically based cattle TSE suggests for the first time that all 3 etiologic forms of TSEs (spontaneous, hereditary, and infectious) may be present in a non-human species. Atypical BSE arising as both genetic and spontaneous disease, in the context of data indicating L-type BSE can convert to classical BSE in mice [27], suggests a cattle origin for classical BSE. This could have occurred either spontaneously or as a result of a polymorphism, such as E211K, that was then amplified by the practice of feeding these affected bovine tissues to cattle. This feeding practice has since been banned in the United States and other nations. Because of the spontaneous and inherited etiology of BSE, eradication is not an attainable goal and a low incidence of BSE can be expected to persist. Compliance with the existing ruminant to ruminant feed ban should, however, prevent another BSE epizootic comparable to that which occurred in the U.K.
Acknowledgments
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http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0002912
> This could have occurred either spontaneously or as a result of a polymorphism, such as E211K, that was then amplified by the practice of feeding these affected bovine tissues to cattle.
> This feeding practice has since been banned in the United States and other nations.
INK ON PAPER, THE AUG. 4, 1997 FDA MAD COW FEED BAN WAS NOTHING BUT INK ON PAPER, IT WAS NOT ENFORCED. ...TSS
10,000,000+ LBS. of PROHIBITED BANNED MAD COW FEED I.E. MBM IN COMMERCE USA 2007
Date: March 21, 2007 at 2:27 pm PST RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINES -- CLASS II ___________________________________
PRODUCT
Bulk cattle feed made with recalled Darling’s 85% Blood Meal, Flash Dried, Recall # V-024-2007
CODE
Cattle feed delivered between 01/12/2007 and 01/26/2007
RECALLING FIRM/MANUFACTURER
Pfeiffer, Arno, Inc, Greenbush, WI. by conversation on February 5, 2007.
Firm initiated recall is ongoing.
REASON
Blood meal used to make cattle feed was recalled because it was cross-contaminated with prohibited bovine meat and bone meal that had been manufactured on common equipment and labeling did not bear cautionary BSE statement.
VOLUME OF PRODUCT IN COMMERCE
42,090 lbs.
DISTRIBUTION
WI
___________________________________
PRODUCT
Custom dairy premix products: MNM ALL PURPOSE Pellet, HILLSIDE/CDL Prot-Buffer Meal, LEE, M.-CLOSE UP PX Pellet, HIGH DESERT/ GHC LACT Meal, TATARKA, M CUST PROT Meal, SUNRIDGE/CDL PROTEIN Blend, LOURENZO, K PVM DAIRY Meal, DOUBLE B DAIRY/GHC LAC Mineral, WEST PIONT/GHC CLOSEUP Mineral, WEST POINT/GHC LACT Meal, JENKS, J/COMPASS PROTEIN Meal, COPPINI – 8# SPECIAL DAIRY Mix, GULICK, L-LACT Meal (Bulk), TRIPLE J – PROTEIN/LACTATION, ROCK CREEK/GHC MILK Mineral, BETTENCOURT/GHC S.SIDE MK-MN, BETTENCOURT #1/GHC MILK MINR, V&C DAIRY/GHC LACT Meal, VEENSTRA, F/GHC LACT Meal, SMUTNY, A-BYPASS ML W/SMARTA, Recall # V-025-2007
CODE
The firm does not utilize a code - only shipping documentation with commodity and weights identified.
RECALLING FIRM/MANUFACTURER
Rangen, Inc, Buhl, ID, by letters on February 13 and 14, 2007. Firm initiated recall is complete.
REASON
Products manufactured from bulk feed containing blood meal that was cross contaminated with prohibited meat and bone meal and the labeling did not bear cautionary BSE statement.
VOLUME OF PRODUCT IN COMMERCE
9,997,976 lbs.
DISTRIBUTION
ID and NV
END OF ENFORCEMENT REPORT FOR MARCH 21, 2007
http://www.fda.gov/bbs/topics/enforce/2007/ENF00996.html
2006
Subject: MAD COW FEED RECALL USA SEPT 6, 2006 1961.72 TONS IN COMMERCE AL, TN, AND WV
Date: September 6, 2006 at 7:58 am PST
PRODUCT
a) EVSRC Custom dairy feed, Recall # V-130-6; b) Performance Chick Starter, Recall # V-131-6; c) Performance Quail Grower, Recall # V-132-6; d) Performance Pheasant Finisher, Recall # V-133-6.
CODE None
RECALLING FIRM/MANUFACTURER
Donaldson & Hasenbein/dba J&R Feed Service, Inc., Cullman, AL, by telephone on June 23, 2006 and by letter dated July 19, 2006. Firm initiated recall is complete.
REASON
Dairy and poultry feeds were possibly contaminated with ruminant based protein.
VOLUME OF PRODUCT IN COMMERCE
477.72 tons
DISTRIBUTION
AL ______________________________
PRODUCT
a) Dairy feed, custom, Recall # V-134-6; b) Custom Dairy Feed with Monensin, Recall # V-135-6. CODE None. Bulk product
RECALLING FIRM/MANUFACTURER
Recalling Firm: Burkmann Feed, Greeneville, TN, by Telephone beginning on June 28, 2006.
Manufacturer: H. J. Baker & Bro., Inc., Albertville, AL. Firm initiated recall is complete.
REASON
Possible contamination of dairy feeds with ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
1,484 tons
DISTRIBUTION
TN and WV
http://www.fda.gov/bbs/topics/enforce/2006/ENF00968.html
Subject: MAD COW FEED RECALLS ENFORCEMENT REPORT FOR AUGUST 9, 2006 KY, LA, MS, AL, GA, AND TN 11,000+ TONS
Date: August 16, 2006 at 9:19 am PST
RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINE - CLASS II ______________________________
PRODUCT
Bulk custom made dairy feed, Recall # V-115-6
CODE None
RECALLING FIRM/MANUFACTURER
Hiseville Feed & Seed Co., Hiseville, KY, by telephone and letter on or about July 14, 2006. FDA initiated recall is ongoing.
REASON
Custom made feeds contain ingredient called Pro-Lak which may contain ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
Approximately 2,223 tons
DISTRIBUTION
KY
______________________________
PRODUCT
Bulk custom made dairy feed, Recall # V-116-6
CODE None
RECALLING FIRM/MANUFACTURER
Rips Farm Center, Tollesboro, KY, by telephone and letter on July 14, 2006. FDA initiated recall is ongoing.
REASON
Custom made feeds contain ingredient called Pro-Lak which may contain ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
1,220 tons
DISTRIBUTION
KY
______________________________
PRODUCT
Bulk custom made dairy feed, Recall # V-117-6
CODE None
RECALLING FIRM/MANUFACTURER
Kentwood Co-op, Kentwood, LA, by telephone on June 27, 2006. FDA initiated recall is completed.
REASON
Possible contamination of animal feed ingredients, including ingredients that are used in feed for dairy animals, with ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
40 tons
DISTRIBUTION
LA and MS
______________________________
PRODUCT
Bulk Dairy Feed, Recall V-118-6
CODE None
RECALLING FIRM/MANUFACTURER
Cal Maine Foods, Inc., Edwards, MS, by telephone on June 26, 2006. FDA initiated recall is complete.
REASON
Possible contamination of animal feed ingredients, including ingredients that are used in feed for dairy animals, with ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
7,150 tons
DISTRIBUTION
MS
______________________________
PRODUCT
Bulk custom dairy pre-mixes, Recall # V-119-6
CODE None
RECALLING FIRM/MANUFACTURER
Walthall County Co-op, Tylertown, MS, by telephone on June 26, 2006. Firm initiated recall is complete.
REASON
Possible contamination of dairy animal feeds with ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
87 tons
DISTRIBUTION
MS
______________________________
PRODUCT
Bulk custom dairy pre-mixes, Recall # V-120-6
CODE None
RECALLING FIRM/MANUFACTURER
Ware Milling Inc., Houston, MS, by telephone on June 23, 2006. Firm initiated recall is complete.
REASON
Possible contamination of dairy animal feeds with ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
350 tons
DISTRIBUTION
AL and MS
______________________________
PRODUCT
a) Tucker Milling, LLC Tm 32% Sinking Fish Grower, #2680-Pellet, 50 lb. bags, Recall # V-121-6; b) Tucker Milling, LLC #31120, Game Bird Breeder Pellet, 50 lb. bags, Recall # V-122-6; c) Tucker Milling, LLC #31232 Game Bird Grower, 50 lb. bags, Recall # V-123-6; d) Tucker Milling, LLC 31227-Crumble, Game Bird Starter, BMD Medicated, 50 lb bags, Recall # V-124-6; e) Tucker Milling, LLC #31120, Game Bird Breeder, 50 lb bags, Recall # V-125-6; f) Tucker Milling, LLC #30230, 30 % Turkey Starter, 50 lb bags, Recall # V-126-6; g) Tucker Milling, LLC #30116, TM Broiler Finisher, 50 lb bags, Recall # V-127-6
CODE
All products manufactured from 02/01/2005 until 06/20/2006
RECALLING FIRM/MANUFACTURER
Recalling Firm: Tucker Milling LLC, Guntersville, AL, by telephone and visit on June 20, 2006, and by letter on June 23, 2006. Manufacturer: H. J. Baker and Brothers Inc., Stamford, CT. Firm initiated recall is ongoing.
REASON
Poultry and fish feeds which were possibly contaminated with ruminant based protein were not labeled as "Do not feed to ruminants".
VOLUME OF PRODUCT IN COMMERCE
7,541-50 lb bags
DISTRIBUTION
AL, GA, MS, and TN
END OF ENFORCEMENT REPORT FOR AUGUST 9, 2006
###
http://www.fda.gov/bbs/topics/ENFORCE/2006/ENF00964.html
Subject: MAD COW FEED RECALL MI MAMMALIAN PROTEIN VOLUME OF PRODUCT IN COMMERCE 27,694,240 lbs
Date: August 6, 2006 at 6:14 pm PST
PRODUCT
Bulk custom dairy feds manufactured from concentrates, Recall # V-113-6
CODE
All dairy feeds produced between 2/1/05 and 6/16/06 and containing H. J. Baker recalled feed products.
RECALLING FIRM/MANUFACTURER
Vita Plus Corp., Gagetown, MI, by visit beginning on June 21, 2006. Firm initiated recall is complete.
REASON
The feed was manufactured from materials that may have been contaminated with mammalian protein.
VOLUME OF PRODUCT IN COMMERCE
27,694,240 lbs
DISTRIBUTION
MI
END OF ENFORCEMENT REPORT FOR AUGUST 2, 2006
###
http://www.fda.gov/bbs/topics/enforce/2006/ENF00963.html
Subject: MAD COW FEED RECALL AL AND FL VOLUME OF PRODUCT IN COMMERCE 125 TONS Products manufactured from 02/01/2005 until 06/06/2006
Date: August 6, 2006 at 6:16 pm PST
PRODUCT
a) CO-OP 32% Sinking Catfish, Recall # V-100-6; b) Performance Sheep Pell W/Decox/A/N, medicated, net wt. 50 lbs, Recall # V-101-6; c) Pro 40% Swine Conc Meal -- 50 lb, Recall # V-102-6; d) CO-OP 32% Sinking Catfish Food Medicated, Recall # V-103-6; e) "Big Jim's" BBB Deer Ration, Big Buck Blend, Recall # V-104-6; f) CO-OP 40% Hog Supplement Medicated Pelleted, Tylosin 100 grams/ton, 50 lb. bag, Recall # V-105-6; g) Pig Starter Pell II, 18% W/MCDX Medicated 282020, Carbadox -- 0.0055%, Recall # V-106-6; h) CO-OP STARTER-GROWER CRUMBLES, Complete Feed for Chickens from Hatch to 20 Weeks, Medicated, Bacitracin Methylene Disalicylate, 25 and 50 Lbs, Recall # V-107-6; i) CO-OP LAYING PELLETS, Complete Feed for Laying Chickens, Recall # 108-6; j) CO-OP LAYING CRUMBLES, Recall # V-109-6; k) CO-OP QUAIL FLIGHT CONDITIONER MEDICATED, net wt 50 Lbs, Recall # V-110-6; l) CO-OP QUAIL STARTER MEDICATED, Net Wt. 50 Lbs, Recall # V-111-6; m) CO-OP QUAIL GROWER MEDICATED, 50 Lbs, Recall # V-112-6
CODE
Product manufactured from 02/01/2005 until 06/06/2006
RECALLING FIRM/MANUFACTURER
Alabama Farmers Cooperative, Inc., Decatur, AL, by telephone, fax, email and visit on June 9, 2006. FDA initiated recall is complete.
REASON
Animal and fish feeds which were possibly contaminated with ruminant based protein not labeled as "Do not feed to ruminants".
VOLUME OF PRODUCT IN COMMERCE
125 tons
DISTRIBUTION
AL and FL
END OF ENFORCEMENT REPORT FOR AUGUST 2, 2006
###
http://www.fda.gov/bbs/topics/enforce/2006/ENF00963.html
Subject: MAD COW FEED RECALL KY VOLUME OF PRODUCT IN COMMERCE ????? Date: August 6, 2006 at 6:19 pm PST
PRODUCT
Bulk custom made dairy feed, Recall # V-114-6
CODE None
RECALLING FIRM/MANUFACTURER
Burkmann Feeds LLC, Glasgow, KY, by letter on July 14, 2006. Firm initiated recall is ongoing.
REASON
Custom made feeds contain ingredient called Pro-Lak, which may contain ruminant derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
?????
DISTRIBUTION
KY
END OF ENFORCEMENT REPORT FOR AUGUST 2, 2006
###
http://www.fda.gov/bbs/topics/enforce/2006/ENF00963.html
CJD WATCH MESSAGE BOARD TSS
MAD COW FEED RECALL USA EQUALS 10,878.06 TONS NATIONWIDE
Sun Jul 16, 2006 09:22
71.248.128.67
RECALLS AND FIELD CORRECTIONS: VETERINARY MEDICINE -- CLASS II
______________________________
PRODUCT
a) PRO-LAK, bulk weight, Protein Concentrate for Lactating Dairy Animals, Recall # V-079-6; b) ProAmino II, FOR PREFRESH AND LACTATING COWS, net weight 50lb (22.6 kg), Recall # V-080-6; c) PRO-PAK, MARINE & ANIMAL PROTEIN CONCENTRATE FOR USE IN ANIMAL FEED, Recall # V-081-6; d) Feather Meal, Recall # V-082-6 CODE a) Bulk b) None c) Bulk d) Bulk
RECALLING FIRM/MANUFACTURER
H. J. Baker & Bro., Inc., Albertville, AL, by telephone on June 15, 2006 and by press release on June 16, 2006. Firm initiated recall is ongoing.
REASON
Possible contamination of animal feeds with ruminent derived meat and bone meal.
VOLUME OF PRODUCT IN COMMERCE
10,878.06 tons
DISTRIBUTION
Nationwide
END OF ENFORCEMENT REPORT FOR July 12, 2006
###
http://www.fda.gov/bbs/topics/enforce/2006/ENF00960.html
Subject: MAD COW FEED BAN WARNING LETTER ISSUED MAY 17, 2006
Date: June 27, 2006 at 7:42 am PST
Public Health Service
Food and Drug Administration
New Orleans District 297 Plus Park Blvd. Nashville, TN 37217
Telephone: 615-781-5380 Fax: 615-781-5391
May 17, 2006
WARNING LETTER NO. 2006-NOL-06
FEDERAL EXPRESS OVERNIGHT DELIVERY
Mr. William Shirley, Jr., Owner Louisiana.DBA Riegel By-Products 2621 State Street Dallas, Texas 75204
Dear Mr. Shirley:
On February 12, 17, 21, and 22, 2006, a U.S. Food & Drug Administration (FDA) investigator inspected your rendering plant, located at 509 Fortson Street, Shreveport, Louisiana. The inspection revealed significant deviations from the requirements set forth in Title 21, Code of Federal Regulations, Part 589.2000 [21 CFR 589.2000], Animal Proteins Prohibited in Ruminant Feed. This regulation is intended to prevent the establishment and amplification of Bovine Spongiform Encephalopathy (BSE). You failed to follow the requirements of this regulation; products being manufactured and distributed by your facility are misbranded within the meaning of Section 403(a)(1) [21 USC 343(a)(1)] of the Federal Food, Drug, and Cosmetic Act (the Act).
Our investigation found you failed to provide measures, including sufficient written procedures, to prevent commingling or cross-contamination and to maintain sufficient written procedures [21 CFR 589.2000(e)] because:
You failed to use clean-out procedures or other means adequate to prevent carryover of protein derived from mammalian tissues into animal protein or feeds which may be used for ruminants. For example, your facility uses the same equipment to process mammalian and poultry tissues. However, you use only hot water to clean the cookers between processing tissues from each species. You do not clean the auger, hammer mill, grinder, and spouts after processing mammalian tissues.
You failed to maintain written procedures specifying the clean-out procedures or other means to prevent carryover of protein derived from mammalian tissues into feeds which may be used for ruminants.
As a result . the poultry meal you manufacture may contain protein derived from mammalian tissues prohibited in ruminant feed. Pursuant to 21 CFR 589.2000(e)(1)(i), any products containing or may contain protein derived from mammalian tissues must be labeled, "Do not feed to cattle or other ruminants." Since you failed to label a product which may contain protein derived from mammalian tissues with the required cautionary statement. the poultry meal is misbranded under Section 403(a)(1) [21 USC 343(a)(1)] of the Act.
This letter is not intended as an all-inclusive list of violations at your facility. As a manufacturer of materials intended for animal feed use, you are responsible for ensuring your overall operation and the products you manufacture and distribute are in compliance with the law. You should take prompt action to correct these violations, and you should establish a system whereby violations do not recur. Failure to promptly correct these violations may result in regulatory action, such as seizure and/or injunction, without further notice.
You should notify this office in writing within 15 working days of receiving this letter, outlining the specific steps you have taken to bring your firm into compliance with the law. Your response should include an explanation of each step taken to correct the violations and prevent their recurrence. If corrective action cannot be completed within 15 working days, state the reason for the delay and the date by which the corrections will be completed. Include copies of any available documentation demonstrating corrections have been made.
Your reply should be directed to Mark W. Rivero, Compliance Officer, U.S. Food and Drug Administration, 2424 Edenborn Avenue, Suite 410, Metairie, Louisiana 70001. If you have questions regarding any issue in this letter, please contact Mr. Rivero at (504) 219-8818, extension 103.
Sincerely,
/S
Carol S. Sanchez Acting District Director New Orleans District
http://www.fda.gov/foi/warning_letters/g5883d.htm
see full text ;
http://madcowspontaneousnot.blogspot.com/2008/02/specified-risk-materials-srm.html
Sunday, March 16, 2008 MAD COW DISEASE terminology UK c-BSE (typical),
atypical BSE H or L, and or Italian L-BASE March 16, 2008
http://bse-atypical.blogspot.com/2008/03/mad-cow-disease-terminology-uk-c-bse.html
> Title: Prevalence of the prion gene E211K variant in U.S. cattle
> Thus, the mutation appears to be either exceedingly rare or non-existent among U.S. purebred, crossbred, beef, and dairy cattle.
SEE STUDY BELOW ;
----- Original Message -----
From: "TERRY SINGELTARY"
To:
Sent: Wednesday, July 16, 2008 10:21 PM
Subject: [BSE-L] Prevalence of the prion protein gene E211K variant in U.S. cattle
-------------------- BSE-L@LISTS.AEGEE.ORG --------------------
Research Project:
Haplotype Structure of the Bovine Prion Gene Complex and Association with Bovine Spongiform Encephalopathy (Bse) Location: Animal Health Systems Research
Title: Prevalence of the prion gene E211K variant in U.S. cattle
Authors
Heaton, Michael Keele, John Harhay, Gregory Richt, Juergen Koohmaraie, Mohammad Wheeler, Tommy Shackelford, Steven Casas, Eduardo King, David Sonstegard, Tad Van Tassell, Curtis Neibergs, Holly - WASHINGTON STATE UNIV. Chase, Chadwick Kalbfleisch, Ted - UNIV. OF LOUISVILLE, KY Smith, Timothy Clawson, Michael Laegreid, William - FORMER ARS EMPLOYEE
Submitted to: BioMed Central (BMC) Veterinary Research Publication Type: Peer Reviewed Journal Publication Acceptance Date: June 10, 2008 Publication Date: July 14, 2008 Citation: Heaton, M.P., Keele, J.W., Harhay, G.P., Richt, J., Koohmaraie, M., Wheeler, T.L., Shackelford, S.D., Casas, E., King, D.A., Sonstegard, T.S., Van Tassell, C.P., Neibergs, H.L., Chase, C.C., Kalbfleisch, T.S., Smith, T.P., Clawson, M.L., Laegreid, W.W. 2008. Prevalence of the prion gene E211K variant in U.S. cattle. BioMed Central (BMC) Veterinary Research 4:25. (http://www.biomedcentral.com/1746-6148/4/25)
Interpretive Summary: Classical bovine spongiform encephalopathy (BSE) is a transmissible fatal brain-wasting disease in cattle. Also known as "mad cow disease," it was first diagnosed in 1986, in the United Kingdom (UK). BSE has since been found in 24 countries including Japan, Canada, and the United States. Consumption of contaminated beef from BSE-affected animals in the UK has been implicated as the most likely cause of a similar disease in humans, variant Creutzfeldt-Jakob Disease (vCJD). However, after regulations were put in place to prevent BSE-contaminated tissues from entering the feed supply and active BSE surveillance was increased, the number of BSE cases dropped dramatically. This was followed by a corresponding reduction in human vCJD cases. A rare type of BSE in cattle, referred to as ¿atypical BSE,¿ has recently been identified and is of interest because it develops in older animals without apparent exposure to other BSE-contaminated material. Although only 30 atypical BSE cases have been identified worldwide, they are significant because of their possible link to other CJDs in humans (i.e., other than vCJD). In 2006, a U.S. case of atypical BSE was discovered in Alabama and later reported to have a mutation (E211K) in the bovine gene required for BSE (i.e., the prion gene). This bovine mutation is strikingly similar to the most commonly inherited defect in humans that causes a type of CJD to develop late in life. This may imply that older cattle with the E211K mutation may also develop atypical BSE late in life. To determine whether this DNA mutation is rare in U.S. cattle, an accurate test was developed and more than 5500 cattle from all parts of the beef and dairy industry were tested for the presence of the mutation. This represents the first prevalence estimate of a mutation that may cause atypical BSE in older animals without prior exposure to BSE-contaminated tissues. None of the cattle tested were found to have the E211K mutation. Thus, the mutation appears to be either exceedingly rare or non-existent among U.S. purebred, crossbred, beef, and dairy cattle.
Technical Abstract: Background: In 2006, an atypical U.S. case of bovine spongiform encephalopathy (BSE) was discovered in Alabama and later reported to be polymorphic for glutamate (E) and lysine (K) codons at position 211 in the bovine prion gene (PRNP) coding sequence. A bovine E211K mutation is important because it is analogous to the most common pathogenic mutation in humans (E200K) which causes hereditary Creutzfeldt - Jakob disease, an autosomal dominant form of prion disease. The present report describes a high-throughput matrix-associated laser desorption/ionization-time-of-flight mass spectrometry assay for scoring the PRNP E211K variant and its use to determine an upper limit for the K211 allele prevalence in U.S. cattle. Results: The K211 allele was not detected in 5690 cattle, including those from five commercial beef processing plants in three states (3892 carcasses) and 1798 registered cattle from 33 breeds. Nearby polymorphisms in PRNP coding sequence of 1084 diverse purebred cattle (33 breeds) did not interfere with scoring E211 or K211 alleles. Based on these results, the prevalence of the E211K variant was estimated to be extremely low, less than 1 in 1900 cattle (Bayesian analysis based on 95% quantile of the posterior distribution with a uniform prior). Conclusion: No groups or breeds of U.S. cattle are presently known to harbor the PRNP K211 variant. Consequently, high-throughput DNA testing may be required to identify carriers and further evaluate this allele as a risk factor for atypical BSE.
http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=223296
Prevalence of the prion protein gene E211K variant in U.S. cattle
Michael P Heaton , John W Keele , Gregory P Harhay , Jurgen A Richt , Mohammad Koohmaraie , Tommy L Wheeler , Steven D Shackelford , Eduardo Casas , D ANDY King , Tad S Sonstegard , Curtis P Van Tassell , Holly L Neibergs , Chad C Chase Jr. , Theodore S Kalbfleisch. , Timothy PL Smith , Michael L Clawson and William W Laegreid
BMC Veterinary Research 2008, 4:25doi:10.1186/1746-6148-4-25
Published: 14 July 2008
Abstract (provisional)
Background
In 2006, an atypical U.S. case of bovine spongiform encephalopathy (BSE) was discovered in Alabama and later reported to be polymorphic for glutamate (E) and lysine (K) codons at position 211 in the bovine prion protein gene (Prnp) coding sequence. A bovine E211K mutation is important because it is analogous to the most common pathogenic mutation in humans (E200K) which causes hereditary Creutzfeldt - Jakob disease, an autosomal dominant form of prion disease. The present report describes a high-throughput matrix-associated laser desorption/ionization-time-of-flight mass spectrometry assay for scoring the Prnp E211K variant and its use to determine an upper limit for the K211 allele frequency in U.S. cattle.
Results
The K211 allele was not detected in 6062 cattle, including those from five commercial beef processing plants (3892 carcasses) and 2170 registered cattle from 42 breeds. Multiple nearby polymorphisms in Prnp coding sequence of 1456 diverse purebred cattle (42 breeds) did not interfere with scoring E211 or K211 alleles. Based on these results, the upper bounds for prevalence of the E211K variant was estimated to be extremely low, less than 1 in 2000 cattle (Bayesian analysis based on 95% quantile of the posterior distribution with a uniform prior).
Conclusion
No groups or breeds of U.S. cattle are presently known to harbor the Prnp K211 allele. Because a carrier was not detected, the number of additional atypical BSE cases with K211 will also be vanishingly low.
http://www.biomedcentral.com/1746-6148/4/25
http://www.biomedcentral.com/content/pdf/1746-6148-4-25.pdf
> This represents the first prevalence estimate of a mutation that may cause atypical BSE in older animals without prior exposure to BSE-contaminated tissues.
i seriously doubt that statement. check out the tonnage of mad cow tainted feed in Alabama as late as 2006, IN COMMERCE.
this spontaneous atypical bse (THAT LOOKS LIKE HUMAN SPORADIC CJD) old cow theory is just more BSe. ...TSS
Wednesday, July 16, 2008
Prevalence of the prion protein gene E211K variant in U.S. cattle
Research Project:
Haplotype Structure of the Bovine Prion Gene Complex and Association with Bovine Spongiform Encephalopathy (Bse) Location: Animal Health Systems Research
Title: Prevalence of the prion gene E211K variant in U.S. cattle
http://bse-atypical.blogspot.com/2008/07/prevalence-of-prion-protein-gene-e211k.html
NEW SOLUTIONS: A Journal of Environmental and Occupational Health Policy
Issue: Volume 18, Number 2 / 2008 Pages: 145 - 156 URL: Linking Options
Mad Cows and Computer Models: The U.S. Response to BSE
Frank Ackerman and Wendy A. Johnecheck
Abstract:
The proportion of slaughtered cattle tested for BSE is much smaller in the U.S. than in Europe and Japan, leaving the U.S. heavily dependent on statistical models to estimate both the current prevalence and the spread of BSE. We examine the models relied on by USDA, finding that the prevalence model provides only a rough estimate, due to limited data availability. Reassuring forecasts from the model of the spread of BSE depend on the arbitrary constraint that worst-case values are assumed by only one of 17 key parameters at a time. In three of the six published scenarios with multiple worst-case parameter values, there is at least a 25% probability that BSE will spread rapidly. In public policy terms, reliance on potentially flawed models can be seen as a gamble that no serious BSE outbreak will occur. Statistical modeling at this level of abstraction, with its myriad, compound uncertainties, is no substitute for precautionary policies to protect public health against the threat of epidemics such as BSE.
http://baywood.metapress.com/app/home/contribution.asp?referrer=parent&backto=issue,5,18;journal,1,41;linkingpublicationresults,1:300327,1
Owner and Corporation Plead Guilty to Defrauding Bovine Spongiform Encephalopathy (BSE) Surveillance Program
PLEASE SEE FULL TEXT ;
Monday, June 16, 2008 Mad Cows and Computer Models: The U.S. Response to BSE
http://bse-atypical.blogspot.com/
In this context, a word is in order about the US testing program. After the discovery of the first (imported) cow in 2003, the magnitude of testing was much increased, reaching a level of >400,000 tests in 2005 (Figure 4). Neither of the 2 more recently indigenously infected older animals with nonspecific clinical features would have been detected without such testing, and neither would have been identified as atypical without confirmatory Western blots. Despite these facts, surveillance has now been decimated to 40,000 annual tests (USDA news release no. 0255.06, July 20, 2006) and invites the accusation that the United States will never know the true status of its involvement with BSE.
In short, a great deal of further work will need to be done before the phenotypic features and prevalence of atypical BSE are understood. More than a single strain may have been present from the beginning of the epidemic, but this possibility has been overlooked by virtue of the absence of widespread Western blot confirmatory testing of positive screening test results; or these new phenotypes may be found, at least in part, to result from infections at an older age by a typical BSE agent, rather than neonatal infections with new "strains" of BSE. Neither alternative has yet been investigated.
http://www.cdc.gov/ncidod/EID/vol12no12/06-0965.htm
Please remember, the last two mad cows documented in the USA i.e. Alabama and Texas, both were of the 'atypical' BSE strain, and immediately after that, the USDA shut down the testing from 470,000 to 40,000 in the U.S. in 2007 out of about 35 million cattle slaughtered.
also, science is showing that some of these atypical cases are more virulent to humans than the typical UK BSE strain ;
***Atypical forms of BSE have emerged which, although rare, appear to be more virulent than the classical BSE that causes vCJD.***
Progress Report from the National Prion Disease Pathology Surveillance Center An Update from Stephen M. Sergay, MB, BCh & Pierluigi Gambetti, MD April 3, 2008
http://www.aan.com/news/?event=read&article_id=4397&page=72.45.45
Sunday, August 10, 2008A New Prionopathy OR more of the same old BSe and sporadic CJD
http://creutzfeldt-jakob-disease.blogspot.com/2008/08/new-prionopathy-or-more-of-same-old-bse.html
PEACE
Terry S. Singeltary Sr. P.O. Box 42 Baycliff, Texas USA 77518
-------------------- BSE-L@LISTS.AEGEE.ORG --------------------
Labels: atypical bse, MAD COW FEED BAN, prion, SPORADIC CJD, USA
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