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avian & livestock genetic test data sheet
Swine AMPKγ3R200Q
mutation (RN-) detection by PCR + RFLP
Test code GS003
- Identification of AMPKγ3R200Q mutation,
also know as "RN-" in pigs, by PCR+RFLP
The presence of a dominant mutation
(sometimes denoted RN-) in Hampshire pigs which
significantly affects meat quality and processing yield was
first recognized by segregation analysis of phenotypic data.
Meat from RN– pigs has a low ultimate pH (measured 24
hours after slaughter), a reduced water-holding capacity, and
gives a reduced yield of cured cooked ham. These characteristics
are due to a ~70% increase in muscle glycogen content in animals
that are homozygous or heterozygous carriers of this mutation
(Scheffler et al., 2016). However, animals with this mutation do
not develop any pathological effects, including any glycogen
storage diseases.
Through extensive sequencing efforts, the mutation has been
characterized to be a non-conservative substitution (R200Q) in
the PRKAG3 gene, which encodes a muscle-specific isoform of the
regulatory γ subunit of adenosine monophosphate activated
protein kinase (AMPK). AMPK is a heterotrimeric serine/threonine
kinase composed of a catalytic α, and regulatory β and γ
subunits. AMPK is activated by an increase in the ratio of AMP
to adenosine triphosphate (AMP:ATP). Activated AMPK turns on
ATP-producing pathways and inhibits ATP-consuming pathways. AMPK
can also inactivate glycogen synthase, the key regulatory enzyme
of glycogen synthesis, by phosphorylation. Several isoforms of
the three different AMPK subunits are present in mammals. The
R200Q mutation is located in the protein domain that is
essential for binding AMP or ATP, and the mutation reduces AMP
dependence and elevates basal activity of AMPK.
This mutation has beneficial effects on meat content but
detrimental effects on processing yield. Most breeders would
like to eliminate the AMPKγ3R200Q
mutation from their herds because of its negative effect on
processing yield. Genetic screening is crucial to select pigs
for future breeding that are clear of the mutation.
Utilities:
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Identify this mutation in swine
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Help remove this mutation from herds
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Enable breeding of pigs with specific genotypic
characteristics
References:
Scheffler, T.L., Park, S., Roach, P.J. and Gerrard, D.E. (2016)
Gain of function AMP-activated protein kinase γ3 mutation
(AMPKγ3R200Q) in pig muscle increases glycogen storage
regardless of AMPK activation. Physiol. Rep. 4: e12802.
Specimen requirements: Buccal swab, or 0.2
ml whole blood in EDTA (purple top) tube, or
0.2 ml fresh, frozen or fixed tissue.
Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.
For all specimen types, if there will be a delay in shipping, or
during very warm weather, refrigerate specimens until shipped
and ship with a cold pack unless more stringent shipping
requirements are specified. Frozen specimens should be shipped
so as to remain frozen in transit. See
shipping instructions for
more information.
Turnaround time: 3 business days
Methodology: PCR + restriction
fragment length polymorphism
Normal range:
Not detected
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