Frequencies of feline blood types in the Rio de Janeiro area of Brazil

Background: The distribution and frequency of blood types in cat populations vary according to geographic region and breed. Frequencies of feline blood types in Rio de Janeiro city, as well as in other Brazilian areas, are unknown, and the risk of unmatched transfusions and neonatal isoerythrolysis has not been estimated. Objectives: The purpose of this study was to determine the frequency of feline blood types in the area of Rio de Janeiro, Brazil. Methods: EDTA blood samples were obtained from 172 nonpedigreed domestic shorthair (DSH) cats (92 female, 80 male, 3 months-20 years old) in different sites of Rio de Janeiro city. Blood typing was performed by agglutination assays using Triticum vulgaris lectin and feline anti-A serum. The hemagglutination results for type B and AB cats were confirmed by high-performance thin-layer chromatography (HPTLC) of erythrocyte membrane gangliosides. Results: The majority (163/172, 94.8%) of cats were type A, 2.9% were type B, and 2.3% were type AB. High-titer anti-A serum agglutinated RBCs from all cats in type A and type AB blood groups, with 3+ to 4+ agglutination. The probability that a type A cat would receive type B or AB blood in a first random transfusion was calculated as 2.25% and 2.20%, respectively. HPTLC analysis of glycolipids yielded a chromatographic profile characteristic of feline gangliosides for all blood groups. Conclusions: These results indicate a high prevalence of type A cats in Rio de Janeiro, Brazil, and a low frequency of type B and AB cats, consistent with what has been observed for DSH cats in other regions of the world.     

Comparison of gel column agglutination with monoclonal antibodies and card agglutination methods for assessing the feline AB group system and a frequency study of feline blood types in northern Italy

Background: A new commercial gel column agglutination system is reported to have high sensitivity in detecting cats with blood type AB. Objectives: The aims of this study were to compare gel column agglutination and card agglutination methods for feline blood‐typing and to determine the frequency distribution of feline blood types in northern Italy. Methods: Blood‐typing was performed on 120 cats using both a commercial gel column containing monoclonal antibodies (ID Gel‐Test Micro Typing System) and a card agglutination method (RapidVet‐H Feline). Results were confirmed with back‐typing. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for the 2 methods. A second group of 140 Domestic Shorthair (DSH) cats was blood‐typed using the gel column technique to determine the frequency distribution of feline blood types in northern Italy. Results: The card agglutination method demonstrated poor sensitivity in identification of type‐AB cats (61%) and was only 95% specific when identifying type‐B cats. The gel column agglutination technique demonstrated 100% sensitivity and specificity for typing all 3 blood types (A, B, and AB). The frequency distribution study of 140 cats demonstrated that 127 (90.7%) cats were type A, 10 (7.1%) were type B, and 3 (2.1%) were type AB. Conclusion: When blood‐typing cats of breeds with a relatively high frequency of blood types B and AB, methods that use monoclonal antibodies for detection of blood types B and AB are recommended. Alternatively, blood type can be confirmed by more sensitive supplemental testing, such as back‐typing. The high frequency of blood type A in DSH cats in northern Italy was comparable to previously reported frequencies in Italy and world‐wide.     

Prevalence of feline blood groups in the Montreal area of Quebec,Canada

The feline AB blood group system has clinical significance because type B cats have natural alloimmune anti-A antibodies which can cause isoerythrolysis of the newborn and life-threatening transfusion reactions. In the United States, the prevalence of type B blood is estimated to be 1% to 2%. This study determined the prevalence of feline AB blood groups among 207 potential blood donor cats that included 178 domestic cats, in the Montreal area of Quebec, Canada. Blood typing was performed using a standardized tube technique. Blood types AB and B were confirmed using a backtyping technique. The frequency of blood types among the studied population was as follows: 95.2% type A, 4.4% type B, and 0.48% type AB. Among domestic cats, the frequency was 94.4% for type A, 5% for type B, and 0.6% for type AB. The frequency of type B was higher than expected, which reinforces the recommendation to ensure blood compatibility of the recipient and donor before transfusion through typing and possibly cross-matching as well.     

Frequencies of feline blood types in northern Portugal

The frequencies of feline blood types in northern Portugal were studied by surveying 185 pedigreed and nonpedigreed cats. Blood typing was performed by the traditional tube method. As a single group, the majority of cats were type A (90.3%), 3.8% were type B, and 5.9% were type AB. Among pedigreed cats, 19 were Siamese and 7 were Persian; all but 1 were type A. Among nonpedigreed cats, 89.3% were type A, 4.4% were type B, and 6.3% were type AB.     

Distribution of Feline Blood Types Detected in the Copenhagen Area of Denmark

Jensen, A. L., A. B. Olesen and J. Arnbjerg: Distribution of feline blood types detected in the Copenhagen area of Denmark. Acta vet. scand., 1994, 35, 121-124.–The purpose of the present study was to make the first survey of the distribution of feline AB blood types in the Copenhagen area of Denmark. A total of 244 cats (139 purebred cats and 105 Domestic Shorthair cats) were tested. 93% of all tested cats had blood type A. Neither an AB nor an O type cat was detected and thus, the frequency of blood type B among all tested cats was 7%. Most type B cats were purebred cats (Birman, British Shorthair and Persian cats). No association between sex and blood type could be demonstrated among British Shorthair and Persian cats. Thus, the present study indicates that cats in Denmark predominantly have blood type A, and that blood type B cats are rare, except for certain breeds such as Birman and British Shorthair cats.     

Blood type A and B frequencies in Turkish Van and Angora cats in Turkey

Blood typing of domestic cats has been performed in domestic and purebred cats in various parts of the world and is important in clinical practice in order to prevent neonatal isoerythrolysis (NI) and acute haemolytic transfusion reactions. Prevalence of blood types vary greatly between breeds of cats. Turkish Van and Angora cats are different breeds that originated in geographically distinct regions of Turkey. The present survey determined the frequency of blood types in these Turkish pedigreed cats in Turkey. Ethylenediaminetetraacetic-acid anti-coagulated blood of a total of 113 Turkish Van and Angora cats were examined for blood typing using a slide and tube agglutination assay. Of the 85 Van cats surveyed, 40% had type A, and 60% had type B blood. Of the 28 Turkish Angora cats, 53.6% had type A, and 46.4% had type B blood. No type AB cats were found between both breeds. There was no significant association between blood types and gender of both Angora and Van cats or eye colours of Van cats (P > 0.05). Although these are limited surveys, the overall prevalence of type B cats in these two breeds was very high compared with the results of previous studies worldwide. It appears likely that blood type incompatibilities responsible for feline NI and transfusion reactions are occurring in these breeds. The risk of transfusion incompatibility in Turkish Angora and Van cats was 46.4 and 60%, respectively. It is therefore strongly recommended to breeders and clinicians that blood typing be performed prior to breeding and transfusing cats.     

Frequencies of feline blood types at a referral hospital in the south east of England

OBJECTIVES: To determine the prevalence of blood types in the feline patients and blood donors of the Queen Mother Hospital for Animals (The Royal Veterinary College, London, UK), that were typed between 2000 and 2004. METHODS: A retrospective study was performed using files of patients and blood donors of the Queen Mother Hospital for Animals seen between January 2000 and November 2004. Commercial blood typing cards were used to determine the blood type. RESULTS: One hundred and fifty-six cats were included in the study; 51 (32.7 per cent) were pedigree and 105 (67.3 per cent) non-pedigree. Of the 51 pedigree cats, the prevalence of blood types was as follows: type A, 42 (82.4 per cent); type B, seven (13.7 per cent) and type AB, two (3.9 per cent). Of the 105 non-pedigree cats, the prevalence of blood types was as follows: type A, 71 (67.6 per cent); type B 32 (30.5 per cent) and type AB two (1.9 per cent). CLINICAL SIGNIFICANCE: The prevalence of type B blood in non-pedigree cats is higher than previously suggested and shows high variability within the UK; because of this, blood typing all feline patients, not only the ones of a breed typically known to have higher prevalence of type B blood before transfusion, is absolutely necessary to avoid a fatal transfusion reaction.     

Assessment of feline blood for transfusion purposes in the Dublin area of Ireland

The prevalence of A, B and AB blood types and of feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV) infection was determined in cats in Ireland, in order to determine risk factors for blood taken for transfusion purposes. EDTA blood samples were available from 137 non-pedigree cats and 39 pedigree cats (91 females and 85 males, aged four months to 15.0 years) in the Dublin area of Ireland. Of the 176 EDTA blood samples obtained, 112 (from 92 healthy cats and 20 sick cats) were tested for the presence of both FIV antibodies and FeLV antigens. Blood typing was performed using an immunochromatographic cartridge (CHROM; Alvedia). Testing for FIV and FeLV was performed by ELISA (SNAP FIV/FeLV Combo Test; Idexx Laboratories). Of the 39 pedigree cats, the majority (38 [97.4 per cent]) was type A, and only one (2.6 per cent) was type B. Of the 137 non-pedigree cats, the majority (116 [84.7 per cent]) was type A, 20 (14.6 per cent) were type B, and one (0.7 per cent) was type AB. Of the 92 healthy cats tested, the prevalence of FIV and FeLV positivity was 4.35 and 1.09 per cent, respectively. None of the 20 sick cats tested was FIV-positive; two (10 per cent) of the 20 sick cats were FeLV-positive.     

Frequencies of feline blood types in Hungary

Feline blood group determination is done as a routine diagnostic method in numerous countries. Blood transfusion reactions and feline neonatal isoerythrolysis (FNI) can be avoided with the identification of different feline blood groups. The present study is the first investigation in Hungary during which 100 cats have been examined from all over the country. These cats were out of six breeds: European domestic shorthair, Persian mix, Persian, Abyssinian, Siamese and British shorthair. In the Hungarian feline population European domestic shorthair are most common but other breeds also occur. European domestic shorthair, Persian mix, Abyssianian, Siamese and British shorthair individuals all belonged to blood type A (100%). Blood type B was found very rarely and only in Persian cats. One-third of the Persian cats were categorised into blood type B, whilst type AB was not found during the study.     

A newly recognized blood group in domestic shorthair cats: the Mik red cell antigen

BACKGROUND: Naturally occurring alloantibodies produced against A and B red cell antigens in cats can cause acute hemolytic transfusion reactions. Blood incompatibilities, unrelated to the AB blood group system, have also been suspected after blood transfusions through routine crossmatch testing or as a result of hemolytic transfusion reactions. HYPOTHESIS: Incompatible crossmatch results among AB compatible cats signify the presence of a naturally occurring alloantibody against a newly identified blood antigen in a group of previously never transfused blood donor cats. The associated alloantibody is clinically important based upon a hemolytic transfusion reaction after inadvertent transfusion of red cells expressing this red cell antigen in a feline renal transplant recipient that lacks this red cell antigen. METHODS: Blood donor and nonblood donor cats were evaluated for the presence of auto- and alloantibodies using direct antiglobulin and crossmatch tests, respectively, and were blood typed for AB blood group status. Both standard tube and novel gel column techniques were used. RESULTS: Plasma from 3 of 65 cats and 1 feline renal transplant recipient caused incompatible crossmatch test results with AB compatible erythrocytes indicating these cats formed an alloantibody against a red cell antigen they lack, termed Mik. The 3 donors and the renal transplant recipient were crossmatch-compatible with one another. Tube and gel column crossmatch test results were similar. CONCLUSIONS AND CLINICAL IMPORTANCE: The absence of this novel Mik red cell antigen can be associated with naturally occurring anti-Mik alloantibodies and can elicit an acute hemolytic transfusion reaction after an AB-matched blood transfusion.     

Comparison of five blood-typing methods for the feline AB blood group system

Objective-To compare the ease of use and accuracy of 5 feline AB blood-typing methods: card agglutination (CARD), immunochromatographic cartridge (CHROM), gel-based (GEL), and conventional slide (SLIDE) and tube (TUBE) agglutination assays. Sample Population-490 anticoagulated blood samples from sick and healthy cats submitted to the Transfusion or Clinical Laboratory at the Veterinary Hospital of the University of Pennsylvania. Procedures-Sample selection was purposely biased toward those from anemic, type B, or type AB cats or those with autoagglutination. All blood samples were tested by use of GEL, SLIDE, and TUBE methods. Fifty-eight samples were also tested by use of CARD and CHROM methods. The presence of alloantibodies in all cats expressing the B antigen as detected by use of any method was also assessed. Results-Compared with the historical gold-standard TUBE method, good to excellent agreement was achieved with the other typing tests: CARD, 53 of 58 (91% agreement); CHROM, 55 of 58 (95%); GEL, 487 of 490 (99%); and SLIDE, 482 of 487 (99%; 3 samples were excluded because of autoagglutination). Four of the samples with discordant test results originated from cats with FeLV-related anemia. Conclusions and Clinical Relevance-Current laboratory and in-clinic methods provide simple and accurate typing for the feline AB blood group system with few discrepancies. Retyping after in-clinic typing with the GEL or TUBE laboratory methods is recommended to confirm any type B or AB cats.     

Comparison of various blood-typing methods for the feline AB blood group system

OBJECTIVE: To compare feline blood-typing results determined by use of the card (CARD), gel (GEL), tube (TUBE), University of Pennsylvania (Penn) tube, and Penn slide tests. SAMPLE POPULATION: Blood samples from 38 healthy cats. PROCEDURES: Blood samples, anticoagulated with EDTA, were screened by use of each blood-typing method according to manufacturers' protocols. RESULTS: On the basis of the standard Penn tube and slide test results, 20, 11, and 7 cats were classified as type A positive, type B positive, and type AB positive, respectively. The same results were obtained with the anti-B and anti-B reagents of the TUBE test. Use of anti-A antibodies of original polyclonal and current monoclonal CARD tests resulted in mostly 2+ to 3+ (scale, 0 to 4+) agglutination reactions with blood samples from type A-positive cats; agglutination reactions with blood samples from type AB-positive cats were weak (1+). The anti-B lectin of the CARD test induced a 2+ to 4+ reaction with blood from all type B- and type AB-positive cats. Use of the GEL test allowed recognition of type A and type B blood samples; following addition of anti-A serum to control columns, type B blood was differentiated from type AB blood. CONCLUSIONS AND CLINICAL RELEVANCE: Use of the in-practice CARD test allows identification of type A- and type B-positive cats, but weak reactions of type AB blood with the anti-A monoclonal antibody raise concerns. The modified GEL and TUBE tests appear to be reliable clinical laboratory methods for feline blood typing.     

Distribution of blood types in a sample of 245 New Zealand non-purebred cats

AIMS: To determine the distribution of feline blood types in a sample of non-pedigree, domestic cats in New Zealand, whether a difference exists in this distribution between domestic short haired and domestic long haired cats, and between the North and South Islands of New Zealand; and to calculate the risk of a random blood transfusion causing a severe transfusion reaction, and the risk of a random mating producing kittens susceptible to neonatal isoerythrolysis.

METHODS: The results of 245 blood typing tests in non-pedigree cats performed at the New Zealand Veterinary Pathology (NZVP) and Gribbles Veterinary Pathology laboratories between the beginning of 2009 and the end of 2014 were retrospectively collated and analysed. Cats that were identified as domestic short or long haired were included. For the cats tested at Gribbles Veterinary Pathology 62 were from the North Island, and 27 from the South Island.

RESULTS: The blood type distribution differed between samples from the two laboratories (p=0.029), but not between domestic short and long haired cats (p=0.50), or between the North and South Islands (p=0.76). Of the 89 cats tested at Gribbles Veterinary Pathology, 70 (79%) were type A, 18 (20%) type B, and 1 (1%) type AB; for NZVP 139/156 (89.1%) cats were type A, 16 (10.3%) type B, and 1 (0.6%) type AB. It was estimated that 18.3–31.9% of random blood transfusions would be at risk of a transfusion reaction, and neonatal isoerythrolysis would be a risk in 9.2–16.1% of random matings between non-pedigree cats.

CONCLUSIONS: The results from this study suggest that there is a high risk of complications for a random blood transfusion between non-purebred cats in New Zealand. Neonatal isoerythrolysis should be considered an important differential diagnosis in illness or mortality in kittens during the first days of life.     

Determination of the prevalence of feline blood types in the UK

The efficacy and diagnostic accuracy of a new desk-top feline blood typing kit was evaluated by comparing the results of the kit with traditional blood typing methods on 35 feline blood samples. The kit was then used to blood type 139 non-pedigree cats from Scotland and the north of England and 207 pedigree cats from throughout the UK. Of the non-pedigree cats, 87.1 per cent were type A, 7.9 per cent were type B and 5.0 per cent were type AB, while of the pedigree cats, 54.6 per cent were type A, 40.1 per cent were type B and 5.3 per cent were type AB. The majority (121 out of 207) of these pedigree cats were British shorthaired, of which 39.7 per cent were type A, 58.7 per cent were type B and 1.6 per cent were type AB. No cats were identified that failed to express the type A and/or type B antigens. The prevalence of type AB cats appears to be higher in this study than previously reported. The prevalence of blood types within specific pedigree breeds in the UK appears to vary from that reported elsewhere.     

Frequencies of feline blood groups in the United States

A survey of AB blood group frequencies among cats in the United States was undertaken, using feline blood typing reagents from Australia. We typed blood of 280 cats of both genders and various breeds within the Philadelphia area and 205 cats at 27 veterinary medical teaching hospitals (most cats had been used as blood donors in 1987) throughout the United States. All but 2 cats had type-A blood. A Himalayan cat in Philadelphia and a domestic shorthair cat from Florida, neither of which had been used as a blood donor, had type-B blood. Plasma of the 2 blood-group-Bcats contained strong isoagglutinins (greater than 1:8 titer) against type-A cells, thereby allowing their detection in a major cross-match test. Approximately 30% of tested plasma samples from blood-group-A cats had weak isoagglutinins (1:2 titer) against type-B cells. This limited survey suggests that cats in the United States, including blood donors, predominantly have type-A blood, and that blood-group-B cats are rare.     

Determination of reference intervals for plasma biochemical values in clinically normal adult domestic shorthair cats by use of a dry-slide biochemical analyzer

OBJECTIVE: To establish reference intervals of plasma biochemical values in healthy adult domestic shorthair (DSH) cats by use of controlled conditions. ANIMALS: 95 healthy client-owned cats. PROCEDURES: Food was withheld from the cats overnight. All blood samples were obtained on the same day, at the same location, and by the same investigator. Blood samples were collected from a cephalic vein into lithium heparin tubes. After centrifugation of blood samples, plasma supernatants were harvested and stored at -20 degrees C until assayed for total proteins, albumin, creatinine, urea, glucose, calcium, phosphates, sodium, chloride, potassium, and CO2 concentrations and alkaline phosphatase and alanine aminotransferase activities. RESULTS: Reference intervals in healthy adult DSH cats were 65 to 85 g/L for total proteins, 27 to 39 g/L for albumin, 89 to 207 micromol/L for creatinine, 6.6 to 11.3 mmol/L for urea, 4.1 to 8.2 mmol/L for glucose, 2.4 to 2.9 mmol/L for calcium, 1.1 to 2.1 mmol/L for phosphates, 153 to 161 mmol/L for sodium, 120 to 127 mmol/L for chloride, 3.3 to 4.2 mmol/L for potassium, 15 to 21 mmol/L for CO2, 32 to 147 U/L for alkaline phosphatase, and 34 to 123 U/L for alanine aminotransferase. CONCLUSIONS AND CLINICAL RELEVANCE: This study provided reference intervals for plasma analytes in adult DSH cats. The influence of potential confounding factors was minimized through use of controlled preanalytic and analytic conditions. However, these results cannot be extrapolated to other feline breeds or used to interpret results from other biochemical analyzers.     

Validation of the Sysmex XT‐2000iV hematology system for dogs,cats, and horses. II. Differential leukocyte counts

Background: The Sysmex XT‐2000iV is a laser‐based, flow cytometric hematology system that stains nucleic acids in leukocytes with a fluorescent dye. A 4‐part differential is obtained using side fluorescence light and laser side scatter. Objective: The purpose of this study was to validate the Sysmex XT‐2000iV for determining differential leukocyte counts in blood from ill dogs, cats, and horses. Methods: Blood samples from diseased animals (133 dogs, 65 cats, and 73 horses) were analyzed with the Sysmex XT‐2000iV (Auto‐diff) and the CELL‐DYN 3500. Manual differentials were obtained by counting 100 leukocytes in Wright‐stained blood smears. Results: Leukocyte populations in the Sysmex DIFF scattergram were usually well separated in equine samples, but were not as well separated in canine and feline samples. Correlation among the Sysmex XT‐2000iV, CELL‐DYN 3500, and manual counts was excellent for neutrophil counts (r ≥.97) and good for lymphocyte counts (r ≥.87) for all three species. Systematic differences between the 3 methods were seen for lymphocyte and monocyte counts. The Sysmex reported incomplete differential counts on 18% of feline, 13% of canine, and 3% of equine samples, often when a marked left shift (>10% bands) and/or toxic neutrophils were present. Eosinophils were readily identified in cytograms from all 3 species. Neither the Sysmex nor the CELL‐DYN detected basophils in the 7 dogs and 5 cats with basophilia. Conclusions: The Sysmex XT‐2000iV automated differential leukocyte count performed well with most samples from diseased dogs, cats, and horses. Basophils were not detected. Immature neutrophils or prominent toxic changes often induced errors in samples from cats and dogs.     

Telomerase activity as a marker for malignancy in feline tissues

OBJECTIVE: To establish the diagnostic significance of the telomeric repeat amplification protocol (TRAP) assay in detecting feline malignancies. SAMPLE POPULATION: Solid tissue specimens collected from 33 client-owned cats undergoing diagnostic or therapeutic procedures at the University of Illinois Veterinary Medical Teaching Hospital between July 1997 and September 1999 and an additional 20 tissue samples were collected from 3 clinically normal control cats euthanatized at the conclusion of an unrelated study. PROCEDURE: The TRAP assay was used for detection of telomerase activity. Each result was compared to its respective histopathologic diagnosis. RESULTS: Twenty-nine of 31 malignant and 1 of 22 benign or normal tissue samples had telomerase activity, indicating 94% sensitivity and 95% specificity of the TRAP assay in our laboratory. CONCLUSIONS AND CLINICAL RELEVANCE: The diagnostic significance of telomerase activity has been demonstrated in humans and recently in dogs by our laboratory. We tested feline samples to determine whether similar patterns of telomerase activity exist. On the basis of our results, the TRAP assay may be clinically useful in providing a rapid diagnosis of malignancy in cats. The telomerase enzyme may also serve as a therapeutic target in feline tumors.     

The prevalence of feline A/B blood types in the Sydney region

OBJECTIVE: To determine the distribution of A/B blood types in pedigree and crossbred cats in the Sydney region, and to estimate the associated risk of administering incompatible blood in an unmatched random transfusion. DESIGN: A prospective/retrospective study of blood specimens collected from both sick and healthy cats. MATERIALS AND METHODS: Blood was collected from 355 cats from the Sydney region over a 12-year period from 1992 to 2003. Specimens were obtained from 187 domestic crossbred cats (short and long-haired) and 168 pedigree cats. The blood type of each cat was determined by one of three different laboratories using standard methods that varied over the duration of the survey. RESULTS: The distributions of blood types obtained by the three laboratories were not significantly different. The prevalence of type-A, type-B and type-AB blood types in crossbred cats was 62%, 36% and 1.6%, respectively. This is the highest percentage of type-B cats so far reported for an outbred population of domestic cats, and is significantly higher than the 26% reported previously for cats in the Brisbane region. The calculated frequency for the type-B allele assuming Hardy-Weinberg equilibrium for this feline population is 0.60; the corresponding frequency of the type-A allele is thus approximately 0.40. The calculated proportion of random transfusions from this population giving rise to an incompatible blood transfusion is 46%, with half of these being life-threatening events. The calculated proportion of random matings from this population at risk for developing neonatal isoerythrolysis is 23%. The distribution of A and B blood types for pedigree cats was in general agreement with data reported previously for cats in North America and Europe, suggesting that the distribution of blood types in these purebred populations is relatively consistent throughout the world. CONCLUSIONS: The prevalence of type B cats in the owned domestic and pedigree cat population is so high that blood typing or cross matching prior to transfusion should be mandatory, except in Siamese/Oriental cats.     

Lack of association between p53 SNP and FISS in a cat population from Germany

One recent study indicates a significant association between certain single nucleotide polymorphisms (SNPs) in the genomic sequence of feline p53 and feline injection‐site sarcoma (FISS). The aim of this study was to investigate the correlation between a specific nucleotide insertion in p53 gene and FISS in a German cat population. Blood samples from 150 German cats were allocated to a control group consisting of 100 healthy cats and a FISS‐group consisting of 50 cats with FISS. All blood samples were examined for the presence of the SNP in the p53 gene. Results found the T‐insertion at SNP 3 in 20.0% of the cats in the FISS‐group and 19.2% of cats in the control‐group. No statistically significant difference was observed in allelic distribution between the two groups. Further investigations are necessary to determine the association of SNPs in the feline p53 gene and the occurrence of FISS.