QTL for the heritable inverted teat defect in pigs.
The mothering ability of a sow largely depends on the shape and function of the mammary gland. The aim of this study was to identify QTL for the heritable inverted teat defect, a condition characterized by disturbed development of functional teats. A QTL analysis was conducted in a porcine experimental population based on Duroc and Berlin Miniature pigs (DUMI). The significant QTL were confirmed by linkage analysis in commercial pigs according to the affected sib pair design and refined by family-based association test (FBAT). Nonparametric linkage (NPL) analysis revealed five significant and seven suggestive QTL for the inverted teat defect in the porcine experimental population. In commercial dam lines five significant NPL values were detected. QTL regions in overlapping marker intervals or close proximity in both populations were found on SSC3, SSC4, SSC6, and SSC11. SSC6 revealed QTL in both populations at different positions, indicating the segregation of at least two QTL. The results confirm the previously proposed polygenic inheritance of the inverted teat defect and, for the first time, point to genomic regions harboring relevant genes. The investigation revealed variation of the importance of QTL in the various populations due to either differences in allele frequencies and statistical power or differences in the genetic background that modulates the impact of the liability loci on the expression of the disease. The QTL study enabled us to name a number of plausible positional candidate genes. The correspondence of QTL regions for the inverted teat defect and previously mapped QTL for teat number are in line with the etiologic relationship of these traits.
Jonas
Elisabeth
E
Institute of Animal Breeding Science, University of Bonn, Endenicher Allee 15, 53115, Bonn, Germany.
Schreinemachers
Heinz-Josef
HJ
Kleinwächter
Tina
T
Un
Cemal
C
Oltmanns
Ina
I
Tetzlaff
Sylvio
S
Jennen
Danyel
D
Tesfaye
Dawid
D
Ponsuksili
Siriluck
S
Murani
Eduard
E
Juengst
Heinz
H
Tholen
Ernst
E
Schellander
Karl
K
Wimmers
Klaus
K
D000818:Animals; D033481:Chromosomes, Mammalian / Q000235:genetics; D003433:Crosses, Genetic; D005260:Female; D008297:Male; D008321:Mammary Glands, Animal / Q000002:abnormalities*; D040641:Quantitative Trait Loci / Q000235:genetics*; D019655:Quantitative Trait, Heritable; D034421:Sus scrofa / Q000235:genetics*