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From: TSS ()
Subject: Identifying Variation in the U.S. Bovine Prion Gene
Date: January 22, 2007 at 8:32 am PST

Identifying Variation in the U.S. Bovine Prion Gene
By Laura McGinnis
January 22, 2007
Do genes affect bovine spongiform encephalopathy—also known as BSE, or "mad cow" disease? Are some cattle more susceptible than others?

To address these and other questions, Agricultural Research Service (ARS) scientists at the U.S. Meat Animal Research Center in Clay Center, Neb., have sequenced the bovine prion gene (PRNP) in 192 cattle that represent 16 beef and five dairy breeds common in the United States.

This work, partially funded by a grant from the U.S. Department of Agriculture's Cooperative State Research, Education and Extension Service, is expanding the understanding of how the disease works.

BSE is a fatal neurological disorder characterized by prions—proteins that occur naturally in mammals—that fold irregularly. Molecular biologist Mike Clawson and his Clay Center colleagues are examining PRNP variation in order to learn if and how prions correlate with BSE susceptibility.

From the 192 PRNP sequences, Clawson and his colleagues have identified 388 variations, or polymorphisms, 287 of which were previously unknown. Some of these polymorphisms may influence BSE susceptibility in cattle.

Comparing PRNP sequences from infected and healthy cattle may enable researchers to identify genetic markers in the prion gene that predict BSE susceptibility. In addition to PRNP, the team is currently sequencing several closely related genes, which will also be tested for their association with BSE.

The prevalence of BSE in the United States is extremely low, but this research could improve understanding of the disease and prepare the cattle industry to respond if another prion disease should arise in the future.

http://www.ars.usda.gov/is/pr/2007/070122.htm

Identifying Variation in the U.S. Bovine Prion Gene

Bovine spongiform encephalopathy—BSE, or mad cow disease—is a serious threat to the U.S. beef industry.

While the first confirmed case of BSE on U.S. soil in December 2003 had little effect on domestic consumption, it carved into our international beef sales. According to USDA’s Economic Research Service, the United States exported only $552 million worth of beef in 2004—down from $2.6 billion in 2002 and $3.1 billion in 2003—a reduction due, in part, to the BSE case.

Are some cattle more susceptible to BSE? Is there a genetic component involved?

To address these and other questions, ARS scientists at the U.S. Meat Animal Research Center (USMARC) at Clay Center, Nebraska, have sequenced the bovine prion gene, PRNP, in 192 cattle representing 16 beef and 5 dairy breeds common in the United States. This work was partially funded by a grant from USDA’s Cooperative State Research, Education, and Extension Service.

Prions are proteins that occur naturally in mammals. BSE is a fatal neurological disorder characterized by irregularly folded prions. Much is unknown about the disease, but scientists recognize a correlation between variations in the PRNP gene in some mammals and susceptibility to transmissible spongiform encephalopathies, such as scrapie in sheep.

“Evidence indicates that this could also be true in cattle,” says molecular biologist Mike Clawson. He is among the USMARC scientists examining PRNP variation to learn if and how different forms, or alleles, of the prion gene correlate with BSE susceptibility.

A thorough characterization of PRNP variation in a U.S. cattle population will provide a reference framework for researchers to use in analyzing PRNP sequences from cattle afflicted with BSE.

From the 192 PRNP genes sequenced, Clawson and his colleagues have identified 388 variations, or polymorphisms, of which 287 were previously unknown. Some of these polymorphisms may influence BSE susceptibility in cattle, he says. Ongoing studies with European collaborators are testing the newly identified variants for association with BSE. If these studies show some cattle to be genetically less susceptible to the disease, this information could shed light on BSE’s transmission and development.

The United States has had only three confirmed cases of BSE. Laboratory tests showed that the second and third of these appear to differ significantly from the first case, says Clawson.

“By comparing the PRNP sequence from BSE-infected cattle to healthy cattle, we may be able to identify genetic markers in the prion gene that predict BSE susceptibility,” he says.

In addition to PRNP, the team is currently sequencing several genes closely related to it. These too will be tested for their association with BSE.

“The prevalence of BSE in the United States is extremely low and is declining worldwide,” Clawson says. “Well-characterized genetic markers that correlate to resistance could improve our understanding of the disease and prepare the cattle industry to respond if another prion disease arises in the future.”—By Laura McGinnis, Agricultural Research Service Information Staff.

This research is part of Animal Health, an ARS National Program (#103) described on the World Wide Web at www.nps.ars.usda.gov.

Michael L. Clawson is at the USDA-ARS Roman L. Hruska U.S. Meat Animal Research Center, P.O. Box 166, Clay Center, NE 68933; phone (402) 762-4342, fax (402) 762-4375.

http://www.ars.usda.gov/is/AR/archive/jan07/bovine0107.htm

http://www.ars.usda.gov/is/AR/archive/jan07/bovine0107.pdf

18 January 2007 - Draft minutes of the SEAC 95 meeting (426 KB) held on 7
December 2006 are now available.

snip...

ITEM 9 - ANY OTHER BUSINESS

snip...

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

64. A member noted that at the recent Neuroprion meeting, a study was
presented showing that in transgenic mice BSE passaged in sheep may be more
virulent and infectious to a wider range of species than bovine derived BSE.
Other work presented suggested that BSE and bovine amyloidotic spongiform
encephalopathy (BASE) MAY BE RELATED. A mutation had been identified in the
prion protein gene in an AMERICAN BASE CASE THAT WAS SIMILAR IN NATURE TO A
MUTATION FOUND IN CASES OF SPORADIC CJD. A study also demonstrated that in a
mouse model it was possible to alleviate the pathological changes of prion
disease by suppressing expression of the prion protein gene after infection.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

NOW PLEASE GO BACK AND READ THAT SECOND PARAGRAPH AGAIN.....TSS

http://www.seac.gov.uk/minutes/95.pdf

PLEASE READ FULL TEXT ;

http://www.cdc.gov/ncidod/EID/vol12no12/06-0965.htm?s_cid=eid06_0965_e

3:00 Afternoon Refreshment Break, Poster and Exhibit Viewing in the Exhibit
Hall

3:30 Transmission of the Italian Atypical BSE (BASE) in Humanized Mouse

Models Qingzhong Kong, Ph.D., Assistant Professor, Pathology, Case Western Reserve
University

Bovine Amyloid Spongiform Encephalopathy (BASE) is an atypical BSE strain
discovered recently in Italy, and similar or different atypical BSE cases
were also reported in other countries. The infectivity and phenotypes of
these atypical BSE strains in humans are unknown. In collaboration with
Pierluigi Gambetti, as well as Maria Caramelli and her co-workers, we have
inoculated transgenic mice expressing human prion protein with brain
homogenates from BASE or BSE infected cattle. Our data shows that about half
of the BASE-inoculated mice became infected with an average incubation time
of about 19 months; in contrast, none of the BSE-inoculated mice appear to
be infected after more than 2 years. ***These results indicate that BASE is
transmissible to humans and suggest that BASE is more virulent than
classical BSE in humans.

6:30 Close of Day One

http://www.healthtech.com/2007/tse/day1.asp

SEE STEADY INCREASE IN SPORADIC CJD IN THE USA FROM
1997 TO 2006. SPORADIC CJD CASES TRIPLED, with phenotype
of 'UNKNOWN' strain growing. ...

http://www.cjdsurveillance.com/resources-casereport.html

There is a growing number of human CJD cases, and they were presented last
week in San Francisco by Luigi Gambatti(?) from his CJD surveillance
collection.

He estimates that it may be up to 14 or 15 persons which display selectively
SPRPSC and practically no detected RPRPSC proteins.

http://www.fda.gov/ohrms/dockets/ac/06/transcripts/1006-4240t1.htm

http://www.fda.gov/ohrms/dockets/ac/06/transcripts/2006-4240t1.pdf

JOURNAL OF NEUROLOGY

MARCH 26, 2003

RE-Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob

disease in the United States

Email Terry S. Singeltary:

flounder@wt.net

I lost my mother to hvCJD (Heidenhain Variant CJD). I would like to

comment on the CDC's attempts to monitor the occurrence of emerging

forms of CJD. Asante, Collinge et al [1] have reported that BSE

transmission to the 129-methionine genotype can lead to an alternate

phenotype that is indistinguishable from type 2 PrPSc, the commonest

sporadic CJD. However, CJD and all human TSEs are not reportable

nationally. CJD and all human TSEs must be made reportable in every

state and internationally. I hope that the CDC does not continue to

expect us to still believe that the 85%+ of all CJD cases which are

sporadic are all spontaneous, without route/source. We have many TSEs in

the USA in both animal and man. CWD in deer/elk is spreading rapidly and

CWD does transmit to mink, ferret, cattle, and squirrel monkey by

intracerebral inoculation. With the known incubation periods in other

TSEs, oral transmission studies of CWD may take much longer. Every

victim/family of CJD/TSEs should be asked about route and source of this

agent. To prolong this will only spread the agent and needlessly expose

others. In light of the findings of Asante and Collinge et al, there

should be drastic measures to safeguard the medical and surgical arena

from sporadic CJDs and all human TSEs. I only ponder how many sporadic

CJDs in the USA are type 2 PrPSc?

http://www.neurology.org/cgi/eletters/60/2/176#535

Diagnosis and Reporting of Creutzfeldt-Jakob Disease

Singeltary, Sr et al. JAMA.2001; 285: 733-734.

http://jama.ama-assn.org/cgi/content/full/285/6/733?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=dignosing+and+reporting+creutzfeldt+jakob+disease&searchid=1048865596978_1528&stored_search=&FIRSTINDEX=0&journalcode=jama

BRITISH MEDICAL JOURNAL

BMJ

http://www.bmj.com/cgi/eletters/319/7220/1312/b#EL2

BMJ

http://www.bmj.com/cgi/eletters/320/7226/8/b#EL1

HOWEVER, WE MUST NEVER forget what old paul brown of cdc said either ;-)

CDC DR. PAUL BROWN TSE EXPERT COMMENTS 2006

The U.S. Department of Agriculture was quick to assure the public earlier
this week that the third case of mad cow disease did not pose a risk to
them, but what federal officials have not acknowledged is that this latest
case indicates the deadly disease has been circulating in U.S. herds for at
least a decade.

The second case, which was detected last year in a Texas cow and which USDA
officials were reluctant to verify, was approximately 12 years old.

These two cases (the latest was detected in an Alabama cow) present a
picture of the disease having been here for 10 years or so, since it is
thought that cows usually contract the disease from contaminated feed they
consume as calves. The concern is that humans can contract a fatal,
incurable, brain-wasting illness from consuming beef products contaminated
with the mad cow pathogen.

"The fact the Texas cow showed up fairly clearly implied the existence of
other undetected cases," Dr. Paul Brown, former medical director of the
National Institutes of Health's Laboratory for Central Nervous System
Studies and an expert on mad cow-like diseases, told United Press
International. "The question was, 'How many?' and we still can't answer
that."

Brown, who is preparing a scientific paper based on the latest two mad cow
cases to estimate the maximum number of infected cows that occurred in the
United States, said he has "absolutely no confidence in USDA tests before
one year ago" because of the agency's reluctance to retest the Texas cow
that initially tested positive.

USDA officials finally retested the cow and confirmed it was infected seven
months later, but only at the insistence of the agency's inspector general.

"Everything they did on the Texas cow makes everything USDA did before 2005
suspect," Brown said. ...snip...end

http://www.upi.com/

AND NOT TO FORGET what the OIG has said time and time again over the years;

http://www.usda.gov/oig/webdocs/50601-10-KC.pdf

BSE WORLD UPDATE

http://www.fda.gov/ohrms/dockets/AC/06/slides/2006-4240S1_1_files/frame.htm

[Docket No. FSIS-2006-0011] FSIS Harvard Risk Assessment of Bovine
Spongiform Encephalopathy (BSE)

http://www.fsis.usda.gov/OPPDE/Comments/2006-0011/2006-0011-1.pdf

THE SEVEN SCIENTIST REPORT ***

http://www.fda.gov/ohrms/dockets/dockets/02n0273/02n-0273-EC244-Attach-1.pdf

PAUL BROWN M.D.

http://www.fda.gov/ohrms/dockets/dockets/02n0273/02n-0273-c000490-vol40.pdf

9 December 2005
Division of Dockets Management (RFA-305)

SEROLOGICALS CORPORATION
James J. Kramer, Ph.D.
Vice President, Corporate Operations

http://www.fda.gov/ohrms/dockets/dockets/02n0273/02n-0273-c000383-01-vol35.pdf

TSS

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