QTL analysis of back fat thickness and carcass pH in an F₂ intercross between Landrace and Korean native pigs.
In this study, we conducted a genome-wide linkage analysis to identify the quantitative trait loci (QTL) that influence back fat thickness and carcass pH in an F(2) intercross between Landrace and Korean native pigs. Eight phenotypes related with back fat thickness and carcass pH were measured in more than 960 F(2) progeny. All experimental animals were subjected to genotypic analysis using 173 microsatellite markers located throughout the pig genome. The GridQTL program, based on the least squares regression model, was used to perform the QTL analysis. We identified 22 genome-wide significant QTL in 9 chromosomal regions (SSC1, 2, 5, 6, 7, 8, 12, 15, and 16) and 29 suggestive QTL in 16 chromosomal regions (SSC2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 14, 15, 16, 17, 18, and X). On SSC5, we detected a QTL affecting back fat thickness that accounted for 4.8 % of the phenotypic variance, which was the highest test statistic (F-ratio = 50.3 under the additive model, nominal P value = 2.5 × 10(-12)) observed in this study. Additionally, we showed that there were significant QTL on SSC16 affecting carcass pH traits. In conclusion, the QTL identified in this study together with associated positional candidate genes could play an important role in determining the genetic structure underlying the variation of back fat thickness and carcass pH in pigs.
Division of Applied Life Science (Brain Korea 21 Program), Graduate School of Gyeongsang National University, Jinju 660-701, South Korea.
Chae-Kyoung
CK
Yoo
Hyun-Tae
HT
Lim
Sang-Hyun
SH
Han
Sung-Soo
SS
Lee
Moon-Suck
MS
Ko
Taeyoung
T
Kang
Jun Heon
JH
Lee
Hee-Bok
HB
Park
In-Cheol
IC
Cho
D000273:Adipose Tissue; D000818:Animals; D003433:Crosses, Genetic; D005260:Female; D056726:Genetic Association Studies; D006863:Hydrogen-Ion Concentration; D008297:Male; D008460:Meat; D009929:Organ Size; D040641:Quantitative Trait Loci; D013552:Swine