Mapping of quantitative trait loci for clinical–chemical traits in swine

Abstract

Clinical-chemical traits are diagnostic parameters essential for characterization of health and disease in veterinary practice. The traits show significant variability and are under genetic control, but little is known about the fundamental genetic architecture of this variability, especially in swine. We have identified QTL for alkaline phosphatase (ALP), lactate (LAC), bilirubin (BIL), creatinine (CRE) and ionized sodium (Na(+)), potassium (K(+)) and calcium (Ca(++)) from the serum of 139 F(2) pigs from a Meishan/Pietrain family before and after challenge with Sarcocystis miescheriana, a protozoan parasite of muscle. After infection, the pigs passed through three stages representing acute disease, subclinical disease and chronic disease. Forty-two QTL influencing clinical-chemical traits during these different stages were identified on 15 chromosomes. Eleven of the QTL were significant on a genome-wide level; 31 QTL were chromosome-wide significant. QTL showed specific health/disease patterns with respect to the baseline values of the traits as well as the values obtained through the different stages of disease. QTL influencing different traits at different times were found primarily on chromosomes 1, 3, 7 and 14. The most prominent QTL for the investigated clinical-chemical traits mapped to SSC3 and 7. Baseline traits of ALP, LAC, BIL, Ca(++) and K(+) were influenced by QTL regions on SSC3, 6, 7, 8 and 13. Single QTL explained up to 21.7% of F(2) phenotypic variance. Our analysis confirms that variation of clinical-chemical traits is associated with multiple chromosomal regions.

Genome‐wide association study for the level of serum electrolytes in Italian Large White pigs

“…Studies carried out on pigs, based on F 2 intercrosses between Pietrain and Meishan and between Landrace and Korean native pigs respectively, reported several QTL for serum Ca 2+ level on four porcine chromosomes (SSC), SSC6, SSC13, SSC14 and SSC18 (Reiner et al . ; Yoo et al . ).…”

“…All these results on SSC13 are in agreement with the confidence interval of a QTL for serum Ca 2+ level reported by Reiner et al . () but may exclude an important role of the calcium‐sensing receptor gene ( CASR ) in affecting this clinical–chemical trait in the investigated pig population. CASR (positioned on SSC13:147 907 932–147 935 070) is one of the main genes whose variability influences the level of this electrolyte in human serum (Kapur et al .…”

QTL analysis of clinical-chemical traits in an F2intercross between Landrace and Korean native pigs

“…Elevated Crea levels occur in conditions that decrease the glomerular filtration (45). The synaptotagmin-1 (SYT1) gene is located in the QTL region in SSC5 for Crea and the orthologous region on HSA 12.…”

“…However, studies on QTL for clinical-chemical traits other than lipid levels are still scarce when it comes to pigs. So far one study addressed QTL for clinical-chemical traits other than lipid levels using an F 2 intercross between Pietrain and Meishan pigs (45). As for QTL analysis of serum lipid levels, Gallardo et al (23, half-sib Duroc population), Chen et al (10, F 2 intercross between White Duroc and Erhualian pigs), and Uddin et al (53, F 2 intercross between Duroc and Pietrain pigs) reported QTL for blood lipid levels.…”

3’-UTR polymorphisms of SETD7 gene associate with economic traits in an F2 population between Landrace and Jeju (Korea) Black pigs

“…The CC homozygotes had thinner backfat for all three calculating points, respectively. However, the marbling scores, which reflect the levels of Several quantitative trait loci (QTL) for meat quality traits including backfat and total body fat (Rohrer, 2000;Edwards et al, 2008) and physiological traits in blood such as alkaline phosphatase activity (Yoo et al, 2012), CD4positive leukocyte number (Wattrang et al, 2005), and bilirubin levels (Reiner et al, 2008) (www.animalgenome.org/ cgi-bin/QTLdb) are mapped at the region on Sus scrofa chromosome 8 (SSC8) where SETD7 is located. Reports of an F 2 population of an intercross between Large White and Chinese Meishan pigs described a significant difference in the levels of backfat thickness (Xu et al, 2007), marbling score, and intramuscular fat percentage (Xu et al, 2005), according to the SETD7 genotypes.…”