Dataset of D-loop Sequences from Mitochondrial Control Region in 21 Indigenous Chicken Breeds of Southwest China

Blood samples were obtained via wing vein puncture, and genomic DNA was extracted using a blood genomic DNA extraction kit.The PCR forward primer was 5'-AAACACCCAAACTCACTAAC-3', and the reverse primer was 5'-CACTGGGATGCGGATACTTGC-3'. The PCR amplification system (50 μL) consisted of: 25 μL of 2 × PCR Master Mix, 1 μL each of 10 μmol/L forward and reverse primers, 2 μL (50–100 ng) of template DNA, and sterilized water added to a final volume of 50 μL. The PCR amplification conditions were as follows: initial denaturation at 95°C for 5 min; followed by 35 cycles of denaturation at 95°C for 30 s, annealing at 56°C for 30 s, and extension at 72°C for 30 s; with a final extension at 72°C for 7 min, and held at 4°C. The PCR products were subjected to bidirectional sequencing.Homology alignment of the complete D-loop region sequences from the 21 indigenous chicken breeds was performed using ClustalX 2.1 software, yielding a total of 1,146 complete mitochondrial D-loop region sequences.