Identification of SNPs of the L-BABP and L-FABP and their Association with Growth and Body Composition Traits in Chicken

Fatty acid-binding proteins (FABPs) are members of lipid-binding proteins that participate in lipid uptake and intracellular transport. This study was designed to investigate the effects of the liver bile acid-binding protein (L-BABP) and the liver fatty acid binding protein (L-FABP) genes on chicken growth and body composition traits. Three SNPs (SNIP 1, SNP2 and SNP3) of the L-BABP and six SNPs (SNP7-SNP9, SNP11-SNP13) of the L-FABP were detected firstly by DNA sequencing. Seven SNPs (SNP6 and SNP15-SNP20) of the L-FABP were detected by DNA sequencing and were found in the chicken genomic databases at the same time. Sequenom MassARRAY was developed to genotype 966 birds from the Northeast Agricultural University F-2 (NEAUF(2)) resource population and the Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF) population. Linkage disequilibrium analysis showed that the L-BABP SNPs appeared to be strongly linked with each other and were located within a haplotype block in both populations. SNP7 and SNP8, SNP12 and SNP13, SNP19 and SNP20 of the L-FABP were in strong linkage disequilibrium, respectively. The L-BABP polymorphisms were significantly associated with body weight (BW) (P<0.05) in the NEAUF2 and the NEAUHLF populations and abdominal fat weight (AFW) and abdominal fat percentage (AFP) (P<0.05) in the NEAUHLF population. The L-BABP diplotypes were significantly associated with BW (P<0.05) in the NEAUF2 and the NEAUHLF populations. There was no consistent association between the thirteen SNPs of the L-FABP and the growth and body composition traits in either the NEAUF2 or the NEAUHLF populations. The research suggests that the L-BABP could be a candidate locus to affect growth traits in chickens.