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Benefits and Uses of Cloning and Other Animal Biotechnologies:
U.S. Perspective
Diane Wray-Cahen, PhDSenior Science Advisor
New Technologies and Production Methods DivisionOffice of Agreements and Scientific Affairs
United States Department of AgricultureWashington, DC, USA
May 2015, Prague
Animal Biotechnologies in Context
Increase Distribution Change Genetic Makeup
Assisted Reproductive Technologies
▪ Artificial insemination (1890s - 1900s)
▪ Embryo transfer (1950s)
▪ In vitro fertilization (1980s)
▪ Sex selection
▪ Embryo splitting
▪ Somatic cell nuclear transfer (Cloning; 1990s)
Genetic Modification
▪ Mass selection▪ Pedigree selection▪ Progeny selection▪ Marker-assisted selection▪ Transgenics (1980s)
(GE Animals)▪ Genome-wide selection▪ Gene Editing (2000s)
CONTINUUM
Best selection of tools in the toolbox . . .
for efficient progress towards sustainable goals
Public misPerception of Cloning Uses
“Perfect Dairy Cow”
CLONING
Expansion of Elite Breeding Stock(clones are for breeding, not eating)
– Conserve and Resuscitate Genetics • Insurance against loss
- Deceased animals - Disease outbreaks
• Steers, geldings (polo ponies), mules • Endangered species, rare breeds
– Increase Genetic Diversity• Superior production animals• Disease resistance• Rare breeds or animals
– Increase rate of introduction of traits into herds• Reduce generation time for genetic progress
Why Clone?
MAN-O-MAN2MAN-O-MAN
• Top dairy sire (produced #1 genomic bull in world)
• Respiratory infection and sick in early life
• Never produced enough semen • Died young
• Produced many more semen doses than Man-O-Man
• Excellent health• Superior quality semen• Semen in high demand globally
Saving Superior Genetics(Man-O-Man2)
- Prime, Yield Grade 1 carcasses identified at slaughter - Muscle tissue collected (dam and sire likely unknown)- Bulls and heifers cloned from muscle to produce breeding stock- Used increase animals producing highest quality meat
Angus bull named Alpha
Prime, Yield Grade 1 carcass: • Pinnacle of genetic success
for beef industry• Occurs 0.03% of the time
From Beef to Breeding Stock(Alpha and the Gammas)
Case Study: Curly Calf Syndrome (Arthrogryposis Multiplex Congenita)
N Bar Primrose 2424 Clones• Leading dam of registered Angus cattle• Does not carry 4 genetic recessives• Positive traits, without lethal recessive• 20 clones
Solution: Cloning used as tool to help eliminate genetic defect from US Angus herds
Precision descendant with curly calf syndrome
2008 GAR Precision 1680• Leading Angus sire• Father of another top sire• Highly desirable traits• Natural mutation identified• Fatal recessive gene• (Not a clone)
What are the Barriers?
US (FDA
)
Japa
n (FSC)
Australia
&
NZ (FSA
NZ)
NZ (NZFSA
)
Australia
Argentina
China
EU (E
FSA)
Fran
ce
UK
Clones 2008 2009 2003 2012 ? 2008 (x 4)
2005 2010
Food Safety: safe as food from conventionally bred animals yes yes yes yes yes yes yes yes not
accessedyes
Labeling:none voluntary none none none none ? N/A
Tracing:none yes
National registry none none ? yes
Moratorium for food:
Voluntary (industry) none
Voluntary (industry) none none yes
Offspring are not clonesFood Safety: same as other
sexually reproduced animals
yes yes yes yes yes yes yes yes yes yes
Tracing:none none none none none none ? none
Risk Assessments of Animal Clones by Country
Risk Assessments Conducted
(year)
No Food Safety Concerns
Concensus: Food products from animal clones (and their offspring) are as safe as food products from conventionally bred animals.
Challenges and Barriers –US Perspective
• Science-based risk assessments . . . non-science-based regulatory decisions
• Focus on production processes, rather than safety of products
• Public uncertainty and concern• Mis-information campaigns
Livestock cloning reported
49%
1%
1%
EU:12%34%
1%
2%
* Data compiled from FAS-PSD, FAOSTAT, Global Trade Atlas, EuroStat
Animal Genetics Trade is Global
Estimated Global Market Share for Bovine Semen (%)Flow of genetics from USA (>$1M in trade)Flow of genetics to the EU
EU: World’sLargest importer of Bovine Semen
51%
• No unique risks (similar to other ARTs); Increased frequency of adverse outcomes
• Most losses in early embryonic period (as with other ARTs)• Embryonic loss is NOT a welfare issue• No increased health risks after early neonatal period • Adult clones as healthy as conventionally-bred animals
• Risks for Offspring are same as for other sexually reproduced animals (no increased risks or frequency)
Risks to Animal Health and Welfare?
• Surrogate dams and fetuses monitored throughout pregnancy by veterinarian (including ultrasound)
• Not all species have increased animal health risks• Efficiency is not a measure of animal welfare• Cloning efficiencies improve with experience and skill
Addressing Welfare Issues
Skill and Experience Matters
Other factors:• Cell lines (DNA)• Ova (egg)• Media choice• Embryo selection• Environmental conditions, etc.
Skill/Practice = Success Rates
Efficiencies for cloning can be comparable to other reproductive technologies like ET and IVF
(Marquezini et al., 2005)
Effects of Technician on Embryo Transfer (ET) Efficiency
Data: Individual ET technicians, who transferred 250 or more embryos in Brazil
32
Animal Biotechnology Advancing
• Identify sequences associated with valued traits
• Genomic selection of sires – Combine with cloning to reduce
generation time
Gene editing • Easy, efficient and inexpensive • Animals not distinguishable
from “natural” breeding
Livestock Genomes Mapped
Dehorning
Polled
Editing Genes to Improve Animal Welfare
All female chicks for laying hens
Editing Genes to Produce More Meat with Fewer Resources, Less Waste
Gene Deletion
(China)Increased muscling (myostatin deletion)
Traits Targeted to Region of Need
Opportunity to utilize and/or combine the most appropriate and targeted tools to meet the challenges of the future
Encourage development of new ideas and innovations . . .
Next Generation . . . More Options, Not Fewer
