Functional study of a genetic marker allele associated with resistance to Ascaris suum in pigs.
Two single nucleotide polymorphisms (SNP TXNIP and SNP ARNT), both on chromosome 4, have been reported to be associated with roundworm (Ascaris suum) burden in pigs. In the present study, we selected pigs with two SNP TXNIP genotypes (AA; n = 24 and AB; n = 24), trickle-infected them with A. suum from 8 weeks of age until necropsy 8 weeks later, and tested the hypothesis that pigs with the AA genotype would have higher levels of resistance than pigs of AB genotype. We used different indicators of resistance (worm burden, fecal egg counts (FEC), number of liver white spots and A. suum-specific serum IgG antibody levels). Pigs of the AA genotype had lower mean macroscopic worm burden (2.4 vs 19.3; P = 0.06), lower mean total worm burden (26.5 vs 70.1; P = 0.09) and excreted fewer A. suum eggs at week 8 PI (mean number of eggs/g feces: 238 vs 1259; P = 0.14) than pigs of the AB genotype, as expected based on prior associations. The pigs were also genotyped at another locus (SNP ARNT) which showed a similar trend. This study provides suggestive evidence that resistant pigs may be selected using a genetic marker, TXNIP, and provides further support to the quantitative trait locus on chromosome 4.
Parasitology and Aquatic Diseases, Department of Veterinary Disease Biology, University of Copenhagen, Dyrlægevej 100, DK-1870 Frederiksberg C, Denmark.
Per
P
Skallerup
Parasitology and Aquatic Diseases, Department of Veterinary Disease Biology, University of Copenhagen, Dyrlægevej 100, DK-1870 Frederiksberg C, Denmark.
Stig M
SM
Thamsborg
Genetics and Bioinformatics, Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, Grønnegårdsvej 3, DK-1870 Frederiksberg C, Denmark.
Claus B
CB
Jørgensen
Section for Bacteriology, Pathology and Parasitology, National Veterinary Institute, Bülowsvej 27, DK-1870 Frederiksberg C, Denmark.
Heidi L
HL
Enemark
Department of Infectious Diseases, Division of Parasitology, Faculty of Medicine, University of Miyazaki, Japan.
Ayako
A
Yoshida
Texas Biomedical Research Institute, 7620 N. W. Loop 410, San Antonio, TX, USA.
Harald H H
HH
Göring
Genetics and Bioinformatics, Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, Grønnegårdsvej 3, DK-1870 Frederiksberg C, Denmark.
Merete
M
Fredholm
Parasitology and Aquatic Diseases, Department of Veterinary Disease Biology, University of Copenhagen, Dyrlægevej 100, DK-1870 Frederiksberg C, Denmark.
Peter
P
Nejsum
D000483:Alleles; D000818:Animals; D001196:Ascariasis / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*; D017165:Ascaris suum / Q000502:physiology*; D060467:Disease Resistance / Q000235:genetics*; D005243:Feces / Q000469:parasitology; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D005838:Genotype; D008099:Liver / Q000469:parasitology; D008168:Lung / Q000469:parasitology; D008297:Male; D010270:Parasite Egg Count; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011817:Rabbits; D013552:Swine; D013553:Swine Diseases / Q000276:immunology* / Q000469:parasitology
D005819:Genetic Markers