Knowledge about structural variation of candidate genes could be
important to improve breeding selection scheme and preserve genetic
variability in livestock species. Leptin (LEP) and melanocortin-4 receptor
(MC4R) genes are involved in the energetic pathway and are obvious
candidate genes for fatness. By sequencing LEP and MC4R genes in 72
pigs belonging to lean (Large White and Duroc), fat (Meishan and
Casertana) breeds and also Wild Boar, 98 polymorphic sites, of which
91 were novel, were found in the Leptin sequence while only the previously
described mutation was found in the MC4R gene. A total of 18
LEP haplotypes were observed and their distribution was unequal
among the breeds. The phylogenetic analysis showed two haplotype
branches distinguishing between lean and fat breeds.