A search for genomic regions affecting birth characters and accretion of weightand backfat was conducted in a Meishan-White Composite reciprocal backcrossresource population. Birth traits analyzed (n = 750) were vigor score, number of nipples, and birth weight. Subsequent measures on gilts and barrows (n = 706) analyzed were weaning weight, 8-wk weight, ADG from 8 to 18 wk of age, ADG from18 to 26 wk of age, 26-wk weight, and backfat over the first rib, last rib, andlast lumbar vertebrae at 14 and 26 (n = 599) wk of age. Feed intake and growthof 92 individually penned barrows were also analyzed. A genomic scan was conducted with microsatellite markers spaced at approximately 20-cM intervals, aleast squares regression interval analysis was implemented, and significancevalues were converted to genomewide levels. No associations were detected fortraits measured at birth except for number of nipples, where one significant and two suggestive regions were identified on chromosomes (SSC) 10, 1, and 3,respectively. Early growth was affected by a region on SSC 1 as evidenced byassociations with weights collected at weaning and 8 wk of age and ADG from 8 to18 wk of age. Other regions detected for early growth rate were on SSC 2, 12,and X. Chromosomal regions on SSC 6 and 7 affected ADG from 18 to 26 wk of age.All measures of backfat were affected by regions on SSC 1 and X, whereas SSC 7 consistently affected backfat measures recorded at 26 wk of age. Suggestiveevidence for QTL affecting backfat at 14 wk of age was also detected on SSC 2,6, 8, and 9. These results have improved our knowledge about the genetics ofgrowth rate and fat accretion at the molecular level in swine.