Allergy information for: Alaska Pollock (Theragra chalcogramma )

  • Name: Alaska Pollock
  • Scientific Name: Theragra chalcogramma
  • Occurrence: Fresh or frozen fish including fish fingers, seafood snacks, fish paste, kamaboko and surimi. Surimi is found in pizza topping and as imitation crab, shrimp, or scallop and also in “meatless” hot dogs, hybrid ham and bologna, sausages, and pepperoni sticks.
  • Allergy Information:

    Allergy to fin fish is relatively common (0.4% of adults in the USA according to one telephone survey), and can be associated with severe symptoms such as anaphylactic shock. Symptoms can also occur after ingestion of only a small quantity of fish with one reported reaction in an individual after receiving a kiss from someone who had recently eaten fish. Allergy to fish is not to be confused with a toxic reaction to histamine in spoiled fish (scombroid fish poisoning).

    Almost all fish allergy seems to involve the protein parvalbumin, which is found in the muscle of most fish. As the parvalbumins are similar in all fish species, individuals allergic to one fish are likely to react to a range of different fish species. Thus after a diagnosis of allergy to one fish species, patients are normally advised to avoid all fin fish. Some individuals also react to frog. Although fin fish and shellfish allergies are not linked, individuals can be allergic to both foods.

    Parvalbumin remains able to cause a reaction after cooking. Thus fish remains allergenic after cooking and other treatments. Fish can be a "hidden" allergen in, for example, pizza toppings. Consequently, the EU labelling regulations require foods containing fish and products thereof to be labelled.

    Supplementary information on Fish Allergy

    Fish and fish products play an important role in human nutrition. Fish is a valuable source of proteins and contains large amounts of healthy fats (so called polyunsaturated fatty acids) and fat-soluble vitamins. However, it also is one of the most common causes of food allergy. Fish allergy is a so-called IgE-mediated food allergy. IgE (Immunoglobulin E) is the allergy antibody.

    Allergy to fish is caused by a reaction to protein in fish meat (muscle). The dominating allergen is a muscle protein called parvalbumin. In professional literature this allergen is often referred to as “Gad c 1” from the Latin name for cod fish Gadus callarias. This major allergen is extremely stable to heat, which means that boiling or frying of fish does not destroy the allergen. Other proteins in fish have been described as allergens, but most reactions to cod (and other fish; see under Related foods) are most likely caused by this one allergen


    Reactions can be severe and even life-threatening. The severity of symptoms may vary according to the amount ingested and the sensitivity of the person. Often the first symptom is irritation and itching in mouth and throat appearing few minutes after the intake. It can be followed by other allergic reactions such as nausea, vomiting, stomach ache, diarrhoea, hives (also called urticaria or nettle rash), swelling under the skin (also called angioedema), itching and reddening of the skin, worsening of eczema, asthma (wheezing, breathlessness, coughing), hay fever (itchy nose and eyes, sneezing/runny nose), swelling of the airways, and sometimes fatal episodes of allergic shock. Usually a combination of several symptoms is seen.

    Spoiled fish can contain a substance called histamine. This is the same substance that is produced by cells of an allergic patient during an allergic reaction. It is involved in the induction of symptoms. Spoiled fish can elicit symptoms in every person having eaten it. The reaction is similar to an allergic reaction, i.e. swelling, hives, wheezing etc., but it is poisoning.

    Related foods (cross-reactions)

    Most information on fish allergy is gathered on codfish. The variety of fish eaten around the world is immense. Despite this, fish species known to cause allergy belong to a few closely related orders: codfish and hake (Gadiformes), mackerel, tuna and perch (Perciformes), salmon and trout (Salmoniformes), plaice and sole (Pleuronectiformes), herring, anchovy and sardine (Clupeiformes), carp and catfish (Cypriniformes), and eel (Anguilliformes). Patients with allergy to codfish are often allergic to the other fish species as well. This can be explained by similarity of the allergen parvalbumin in all fish species. Allergic reactions based on such similarity are called cross-reactions. The cross-reactivity between fish species is certainly not complete. Some patients are allergic to one and tolerate other species.

    Allergy to fish does not mean that other seafood like shellfish is not tolerated. Cross-reactivity is irrelevant between fish and shellfish. Of course, patients can develop allergy to both independently. Fish roe (or caviar) has been reported to cause food allergy but there is no relation to allergy to the fish from which the eggs originate.

    Finally, it has been reported that parvalbumin in frogs legs can in some cases also cause allergy in fish allergic patients. This again is cause by cross reactivity.

    Who, when, how long and how often?

    Food allergy to fish is seen both among children and adults (approximately 0.1-0.2%). Varieties in food habits according to country influence the frequency patterns of fish allergy, with the number of fish allergics being higher in those countries where fish is a major component of the local diet. In general, fish allergy is not outgrown but it persists through life.

    How much is too much?

    Care has to be taken since very small amounts (few mg, in other words a tiny flake) of fish can elicit a reaction in very sensitive persons. A dose of only 5 mg of cod has been described to cause reaction. Furthermore, some fish allergic persons can get allergic symptoms due to the steam (airborne allergens) from cooking fish. Fish allergy is therefore sometimes a problem in the fish industry and among restaurant cooks, where handling and inhalation might cause eczema and asthma. Finally, even a kiss of somebody that has eaten fish can induce a reaction in a fish allergic person.


    An indication for IgE-mediated fish allergy can be obtained from skin prick testing and from serum IgE testing. The presence of a positive skin prick test or of fish protein-specific IgE-antibody in serum is indicative of an IgE-mediated fish allergy, but both tests may be false-positive or false-negative. Therefore, a definitive diagnosis has to be based on strict, well-defined elimination and re-introduction protocols or on controlled fish challenge procedures. Fish allergy is confirmed if symptoms disappear after elimination and re-appear upon re-introduction or if a so-called double-blind placebo controlled food challenge gives a positive result. During such a challenge both doctor and patient do not know which challenge meal contains fish and which does not. Such challenge procedures are also helpful in determining the threshold dose of reactivity, and to verify if a person has outgrown the food allergy, although this is rarely seen with fish allergy.

    Where do I find fish?

    It is important to study the labels on processed foods since various products can contain fish: surimi (fish product imitating crabmeat), fish meal, animal fat, liver pâté, some sausages, crab salad, sushi, oyster sauce, Worcestershire sauce, Caesar salad, tapenade, and pizza toppings. Fish oils/animal oil can also contain fish proteins, depending on the degree of refining of the oil. Fish gelatine made from skin and bones and used in food products is not considered to present a risk to fish allergic persons at the doses typically used.

    Non-food products

    Fish gelatine is applied in pharmaceutical products like vaccines, but it is not considered a risk to fish allergic persons.


    If suffering from fish allergy, strict avoidance of fish in any form and food containing fish-derived ingredients is the only way to prevent a reaction. This can sometimes be difficult because they can be hidden in food products. According to the new EU labelling directive (2003/89/EC) and the list of the Codex Alimentarius Commission, any fish-derived ingredient has to be listed on the label. Even if labels are carefully read, unintentionally and accidentally consumption of fish may happen. Fish allergic individuals should especially be cautious when eating away from home. When ordering a “non-fish meal” at a restaurant it may be contaminated with fish proteins from utensils, cooking oil or a grill exposed to fish.

  • Other Information:

    Fish and products thereof are listed in annex IIIa of the EU directive on labelling of foods.

    Theragra chalcogramma is called Alaska pollock or walleye pollock. Pollock and pollack are alternative spellings. The name Theragra fucensis has also been used.

  • Taxonomic Information: NEWT 48550, ITIS 164722
  • Last modified: 18 October 2006

Reviews (0)

    References (0)

      Clinical History

      • Number of Studies:1-5
      • Number of Patients:21-50
      • Symptoms:Helbling et al. (1996) [1727] describe the symptoms of 39 fish allergic patients to 20 fish species. Only 2/39 specifically noted pollack as causing symptoms. However,  pollack was third to anchovy and perch in the number of positve skin tests and after perch, sole, salmon and whitefish in the number of positive RAST tests. Thus symptoms for all 39 patients with fish can be listed as pruritus (27/39), hives (27/39), asthma and wheezing (21/39), angioedema (20/39), dyspepsia and cramps (7/39), vomiting (3/39), shock (3/39) and fainting (2/39).

      Skin Prick Test

      • Number of Studies:1-5
      • Food/Type of allergen:Helbling et al. (1996) [1727] made an extract of Alaska pollack (and of anchovy, mackerel, rainbow trout, salmon and tuna) by blending 500g of raw fish in 1L of 0.01M PBS, pH 7.2, in a Waring blender for 1-3 minutes at room temperature. The mixture was extracted overnight at 4°C and centrifuged (70,000 g). Supernatants were concentrated  with an Amicon YM1 filter (molecular weight cut-off 1 kDa) and recentrifuged (180,000 g). The extracts were sterile filtered and checked for sterility. Samples were diluted to 10 mg./ml. with sterile glycerol.  4 crustacea were extracted similarly except that the flesh was initially boiled for 15 minutes. Results were compared with 16 commercial extracts of fish as well as 12 inhalant allergens.
      • Protocol: (controls, definition of positive etc)

        Helbling et al. (1996) [1727] defined a positive skin prick as producing a 3 mm diameter wheal in a patient who reacted to the positive control (1 mg/ml histamine diphosphate) and not to 50% glycerol in PBS. Results were recorded after 15 minutes.

      • Number of Patients:Helbling et al. (1996) [1727] tested 35 subjects.
      • Summary of Results:Helbling et al. (1996) [1727] found that 18/35 fish allergic subjects gave a positive skin test to pollack.

      IgE assay (by RAST, CAP etc)

      • Number of Studies:0
      • Food/Type of allergen:

        Van Do et al. (2004) [1364] used extracts and purified parvalbumins from Alaska pollack and cod. Recombinant pollack parvalbumin was also used.

        Helbling et al. (1996) [1727] used the same extract as for skin prick testing without sterile filtration or dilution with glycerol.

      • IgE protocol:

        Van Do et al. (2004) [1364] used CAP FEIA and immunoblotting.

        Hamada et al. (2000) [1725] used ELISA.

        Helbling et al. (1996) [1727] used RAST and RAST inhibition.

      • Number of Patients:

        Van Do et al. (2004) [1364] used tested 12 sera from patients with clinical histories of fish allergy and 3 control sera. 6 sera from patients with clinical histories of fish allergy, positive skin prick test, and CAP FEIA classes 4–5 were used for immunoblotting.

        Hamada et al. (2000) [1725] used sera from 2 fish allergic patients.

        Helbling et al. (1996) [1727] tested 21 fish allergic patients with pollack extract out of 39 total patients.

      • Summary of Results:

        Van Do et al. (2004) [1364] report that the 12 sera were CAP FEIA classes 3–5.  The concentration required for obtaining 50% inhibition of IgE-binding to cod parvalbumin was 18% higher for pollack parvalbumin than Gad c 1 itself. Recombinant pollack parvalbumin bound IgE 1000 times less strongly than the native allergens. 

        Hamada et al. (2000) [1725] tested fish meat paste products (kamaboko, tubular kamaboko called chikuwa, boiled kamaboko called hampen, square shaped fried kamaboko called satsuma-age, fish ball called tsumire and fish sausage) and surimi from walleye (Alaska) pollack. IgE from one serum bound only to fish ball. IgE from the other patient bound to all the products and was shown to bind to fish collagen.

        Helbling et al. (1996) [1727] report a positive RAST with sera from 12/21 patients. This is similar to RAST results with several other fish extracts with the same patients such as bass (7/12), catfish (11/21), cod (8/12), flounder (12/21), haddock (8/11), herring (9/22), mackerel (9/23), perch (13/24), salmon (13/24), snapper (11/21), trout (11/22) and whitefish (13/24). However, extracts from anchovy (4/29) and tuna (5/27) showed fewer responses. RAST inhibition studies showed similar cross-reactivity with tuna extract as the least effective inhibitor.


      • Immunoblotting separation:Van Do et al. (2004) [1364] followed the procedure of Laemmli (1970) [948] with a 15% acrylamide separating gel at 200 V (Van Do et al. 2003) [1367] .
      • Immunoblotting detection method:Van Do et al. (2004) [1364] transferred proteins onto nitrocellulose membranes (0.45 µm, Schleicher and Schuell, Dassel, Germany) in a mini trans-blot cell (BIO-RAD) for 1 h at 100 V. These were incubated overnight with 1:4 v/v diluted sera and IgE binding was revealed by antibody binding and BCIP/NBT (SIGMA FAST™).
      • Immunoblotting results:Van Do et al. (2004) [1364] show that all 6 sera bound to a band at 12 kDa in both pollack and cod extract. Purified pollack parvalbumin ran at this position and also bound the IgE.

      Oral provocation

      • Number of Studies:0
      • Food used and oral provocation vehicle:
      • Blind:
      • Number of Patients:
      • Dose response:
      • Symptoms:No oral provocation reported with Alaska pollack

      IgE cross-reactivity and Polysensitisation

      Helbling et al. (1996) [1725] found that 18/35 fish allergic subjects gave a positive skin test to pollack and 12/21 gave a positive RAST. Thus reaction was slightly more common to pollack than to most of the 20 fish tested. RAST inhibition suggested strong IgE cross-reactivity between salmon, pollack, trout and tuna.

      Other Clinical information

      Alaska or walleye pollack is the fish most sold by weight as fresh or frozen in the USA and perhaps second only to tuna overall ( It is the fish most often used to make fish paste or surimi, although surimi is also made from cod (Mata et al. 1994 [1728]). Surimi has been reported as a hidden allergen as both pizza topping (Helbling et al. 1992 [1724]) and as imitation crab meat (Musmand et al. 1996 [1726]). Musmand et al. note that surimi is used as an ingredient for imitation crab, shrimp, scallops, and seafood snacks and also surimi-meat blend products, such as “meatless” hot dogs, hybrid ham and bologna, sausages, pepperoni sticks, and pizza toppings.

      Reviews (2)

      • Wild LG, Lehrer SB.
        Fish and shellfish allergy.
        Curr Allergy Asthma Rep. 5(1):74-79.. 2005
        PUBMEDID: 15659268
      • Taylor, S. L., Kabourek, J. L., Hefle, S. L.
        Fish allergy: Fish and products thereof
        Journal of Food Science 69 (8) R175-R180.. 2004

      References (9)

      • Hamada Y, Genka E, Ohira M, Nagashima Y, Shiomi K
        [Allergenicity of fish meat paste products and surimi from walleye pollack] Japanese
      • Van Do T, Hordvik I, Endresen C, Elsayed S.
        Characterization of parvalbumin, the major allergen in Alaska pollack, and comparison with codfish Allergen M.
        Mol Immunol. 42(3):345-353.. 2005
        PUBMEDID: 15589323
      • Musmand JJ, Helbling A, Lehrer SB.
        Surimi: something fishy.
        J Allergy Clin Immunol. 98(3):697-699.. 1996
        PUBMEDID: 8828548
      • Helbling A, McCants ML, Musmand JJ, Schwartz HJ, Lehrer SB.
        Immunopathogenesis of fish allergy: identification of fish-allergic adults by skin test and radioallergosorbent test.
        Ann Allergy Asthma Immunol. 77(1):48-54.. 1996
        PUBMEDID: 8705636
      • Mata E, Favier C, Moneret-Vautrin DA, Nicolas JP, Han Ching L, Gueant JL.
        Surimi and native codfish contain a common allergen identified as a 63-kDa protein.
        Allergy 49(6):442-447. . 1994
        PUBMEDID: 7521143
      • Van Do T, Hordvik I, Endresen C, Elsayed S.
        The major allergen (parvalbumin) of codfish is encoded by at least two isotypic genes: cDNA cloning, expression and antibody binding of the recombinant allergens.
        Mol Immunol. 39(10):595-602.. 2003
        PUBMEDID: 12431393
      • Laemmli UK
        Cleavage of structural proteins during the assembly of the head of bacteriophage T4
        Nature 227:680-685. 1970
        PUBMEDID: 5432063
      • Van Do T, Elsayed S, Florvaag E, Hordvik I, Endresen C.
        Allergy to fish parvalbumins: studies on the cross-reactivity of allergens from 9 commonly consumed fish.
        J Allergy Clin Immunol. 116(6):1314-1320.. 2005
        PUBMEDID: 16337465

      Biochemical Information for Parvalbumin

      • Allergen Name:Parvalbumin
      • Alternatve Allergen Names:The c 1 (not in IUIS list)
      • Allergen Designation:None
      • Protein Family:EF hand calcium binding proteins, Pfam PF00036; efhand.
      • Sequence Known?:Yes
      • Allergen accession No.s:

      • 3D Structure Accession No.:N/A
      • Calculated Masses:11376 Da and 11496 Da
      • Experimental Masses:12 kDa
      • Oligomeric Masses:Not known
      • Allergen epitopes:Not known. Bugajska-Schretter et al. (1998) [1318] show that IgE binding to carp beta-parvalbumin is very much stronger in the presense of calcium, when the protein is in its native folded form, suggesting that the epitopes are primarily conformational.
      • Allergen stability:
        Process, chemical, enzymatic:
        Most parvalbumins quickly refold in the presence of calcium and thus allergenicity survives cooking.
      • Nature of main cross-reacting proteins:There is clear IgE cross-reactivity between cod and Alaska Pollack parvalbumin. Van Do et al. (2004) [1364] report that the concentration required for obtaining 50% inhibition of IgE-binding to cod parvalbumin was 18% higher for pollack parvalbumin than Gad c 1 itself.
      • Allergen properties & biological function:Parvalbumins control the flow of calcium from troponin C back to membrane bound pumps after a muscle contraction. Each parvalbumin can bind two calcium or (with lower affinity) magnesium ions.
      • Allergen purification:

        Van Do et al. (2004) [1364] report a purification of native parvalbumin by anion exchange chromatography using DEAE cellulose equilibrated with 100 mM phosphate buffer pH 5.4.  A step elution was used with 150 mM buffer and followed by size exclusion chromatography on Sephadex G-75.  Analytical RP/HPLC showed two similar peaks and SDS-PAGE showed a single band. They also expressed two DNA sequences cloned using primers from salmon and cod sequences in E. coli (one cut short by a stop codon). However, the recombinant allergens bound IgE 1000 times less strongly than the native allergens. 

      • Other biochemical information:

        There are two families of beta-parvalbumin sequences in several fishes. One group includes Q90YK7 (Alaska pollack), Q91482 (salmon) and Q90YK9 (cod) and the other Q90YK8 (Alaska pollack), Q91483 (salmon) and Q90YL0 (cod). Each groups shares approximately 75% sequence identity and each sequence has 65-67% sequence identity with members of the other group. Q90YK7 and Q90YK8 are 67% identical.

        3-D structures are available of beta-parvalbumins from carp, Cyprinus carpio, 4CPV, whiting, Merlangius merlangus, 1A75, silver hake, Merluccius Bilinearis, 1BU3, and pike, Esox lucius, 1PAL.

      References (2)

      • Van Do T, Hordvik I, Endresen C, Elsayed S.
        Characterization of parvalbumin, the major allergen in Alaska pollack, and comparison with codfish Allergen M.
        Mol Immunol. 42(3):345-353.. 2005
        PUBMEDID: 15589323
      • Bugajska-Schretter A, Elfman L, Fuchs T, Kapiotis S, Rumpold H, Valenta R, Spitzauer S.
        Parvalbumin, a cross-reactive fish allergen, contains IgE-binding epitopes sensitive to periodate treatment and Ca2+ depletion.
        J Allergy Clin Immunol. 101(1 Pt 1):67-74.. 1998
        PUBMEDID: 9449503