Mapping Gene Loci Of Growth And Coat Traits In Rabbits By Microsatellite Markers

The QTL mapping for important economic traits in rabbit has contribution of positional cloning and rabbit breeding. We screened the rabbit genome with microsatellite markers, and performed QTL mapping on growth and Coat traits in rabbits. F2 and backcross design were used to create resource families with meat rabbit and rex rabbit. A referenc population of 433 rabbits comprising eighty-four three-generation families with 1-10 offspring per family was produced. 14 traits were measured including 13 quantitative traits that were body weight at 60 d (BW60), body weight at 90 d (BW90), body weight at 120 d (BW120), body length at 90 d, chest measurement at 90 d, hip measurement at 90 d, wool length at 90 d, body length at 120 d, chest measurement at 120 d, hip measurement at 120 d, wool length at 120 d, average daily gain from 60 d to 90 d and average daily gain from 90 d to 120 d respectively, and one qualitative trait that was the phenotype of coat.With the principle of more alleles and ploymorphic, we screened 10 microsatellite markers from chromosome 1, 2 and 15. The average heterozygosity is 0.5344946, and PIC is 0.47936465.We used the QTL-express sorftware online which is based on the regression analysis to perform QTL mapping on chromosome 1, 2 and 15.A QTL region which located nearby the microsatellite mark INRACCDDV0192 (toward centromere 13cM~35cM) was found to have effect on BW90 (LOD=4.146), BW120 (LOD=3.689), hip circumference at 120 d (LOD=3.522) and average daily gain from 60 d to 90 d (LOD=3.59). The LOD values of remaining traits on each chromosome are less than 3. Heigher additive effect has been found with BW90, BW120, hip measurement at 120 and average daily gain from 60 d to 90 d, and the the corresponding F test has significant level. In addition,BW90 on chromosome 1, hip circumference at 90 d on chromosome 2, wool length at 90 d on chromosome 1, body length at 120 d on chromosome 2, wool length at 120 d on chromosome 2 and average daily gain from 60 d to 90 d on chromosome 1 has significant level of F test, and their LOD scores are 2.66,2.846,2.589,2.632,2.72 and 2.48 , respectively. The LOD score of coat trait is less than three on every chromosome, the corresponding F test has not significant level.