Table 2. Genotypic and allelic frequency at the SNP ESR1 and ESR2 loci in the Dagu chicken population.

SNP	Genotype	No. of chickens	Genotype frequency	Allele	Allele frequency	χ2
T1101C (ESR1)	TT	287	0.797	T	0.898	4.773 a
	CT	73	0.203	C	0.102
G1755A (ESR2)	GG	251	0.697	G	0.849	9.123 a
	GA	109	0.303	A	0.151

a) P<0.05 was accepted as statistically significant when the data were analyzed using a Pearson’s goodness-of-fit chi-square test (degree of freedom=1).