Submitted to: Probe
Publication Type: Abstract Only
Publication Acceptance Date: November 29, 1996
Publication Date: N/A
Technical Abstract: Chromosomal regions associated with several important traits in swine have been identified. The first example of the use of molecular genetics to control the distribution of a mutation having an economic effect in swine was the discovery and use as a marker a single point mutation in the ryanodine receptor gene (RYR 1). RYR 1 causes porcine stress syndrome in the homozygous state and appears tightly linked to a gene or genes involved in the determination of carcass leanness. Evidence for QTLs with major effects on growth from birth to 70 kg, average backfat depth, length of small intesting, and abdominal fat percentage has been found. The QTLs affecting backfat depth and abdominal fat appear to lie between ms S0001, physically localized to 4p12-4p13 and ATP1B1, physically assigned to 4113-q21. The effect on intestinal length lies between ms S0107 (physically anchored to 4q12) and GBA (glucosidase beta; acid), which is 16 cM distal to S0107. A major effect on growth was reported to be distal to GBA. However, Andersson et al. (1994) were not able to exclude the possiblility that one QTL, located on SSC 4, has pleiotropic effects on all these traits. Several large gaps appear in the most current maps of those regions. A gap of 12 cM appears between SW58 and S0097, and a 19 cM interval lies between SW512 and SW524. This illustrates that even within relatively high resolution maps additional markes are essential to refine the positions(s) of QTL.