Search

The quantitative traits of mass and percentage of abdominal fat in chicken and various types of obesity in mammals are homologous and functionally similar. Therefore, the genes involved in obesity development in humans and laboratory rodents as well as those responsible for pig lard thickness could be involved in abdominal fat deposition in broilers. Expression of candidate genes FABP1, FABP2, FABP3, HMGA1, MC4R, PPARG, PPARGC1A, POMC and PTPN1 was studied in fat, liver, colon, muscle, hypophysis, and brain in chicken (broilers) using real-time PCR. Significant difference in the HMGA1 gene expression in the liver of broiler chicken with high (3.5 +/- 0.18%) and low (1.9 +/- 0.56%) abdominal fat concentration has been revealed. The expression of this gene was been shown to correlate with the amount (0.7, P < or = 0.01) and mass (0.7, P < or = 0.01) of abdominal fat. The PPARG gene expression in liver in the same chicken subsets was also significantly different. Correlation coefficients of the gene expression with the abdominal fat amount and mass were respectively 0.55 (P < or = 0.05) and 0.57 (P < or = 0.01). Based on these results, we suggest that the HMGA1 and PPARG genes are involved in abdominal fat deposition. The search for single nucleotide polymorphisms (SNPs) in the HMGA and PPARG regulatory regions could facilitate identifying genetic markers for broiler breeding according to the mass and percentage of abdominal fat.

PCR amplification of the six fragments of regulatory and coding regions of chicken ChEST985k21 gene (accession no. CR523443), substantially affecting the egg shell thickness quantitative trait, was carried out. Sequencing of these fragments in six chickens from a native Polish breed, Green-legged Partridgenous, with different manifestation of the trait of interest enabled identification of six single nucleotide polymorphism (SNP) sites within the ChEST985k21 sequence. Five of these sites were located in the regulatory region, and one site, in the coding region. For all SNPs identified, the existence of transcription factor binding sites, present in only one allelic variant, was demonstrated. This finding enables considering these sites as regulatory single nucleotide polymorphisms, rSNP. The effect of rSNP discovered on the chicken egg shell thickness was tested using PCR amplification with allele-specific primers. In the groups of chicken of Rhode Island Red breed with thick (389.9 +/- 13.09 microm) and thin (315.7 +/- 21.38 microm) egg shells statistically significant differences in the allele frequencies of the ST2&#95;1, ST3&#95;1, ST3&#95;2, and ST3&#95;3 polymorphic loci. In the same groups of birds, statistically significant differences in the shell thickness were observed in the rSNP allele genotypic classes ST2&#95;1, ST3&#95;1, ST3-2, ST3&#95;3, and ST6&#95;1. Based on these data, it was concluded that rSNPs influenced manifestation of the quantitative trait examined, and the genotyping system for marker assisted selection was constructed.