Developmental expression of MAFbx and P311. Expression of (A) MAFbx and (B) P311 at different stages of embryonic/foetal development (14, 21, 35, 49, 63, 77 and 91 days of gestation), in 24-week-old (adult) pigs, in 2-day-old PCS piglets and corresponding normal litter mates (Norm) were determined. Embryonic/foetal and adult cDNAs were pooled samples from 3 individuals. PCS and Norm cDNAs were pooled from the LD muscles of the 4 sets of litter mates. Expression of MAFbx was detected at basal levels throughout gestation and into adulthood but was elevated in PCS muscles. P311 expression showed rising levels throughout development. However, its expression in PCS piglets was much reduced. Results expressed as mean ± standard deviation from triplicate samples within the same experiment. Norm = normal; PCS = porcine congenital splayleg.