Chen KuanWei

The genetic diversity and origin of Chinese game chicken.

In order to reveal the genetic diversity and origin of Chinese game chicken, a total of 535 base pairs of mitochondrial cyt b gene of five game chicken breeds (40 individuals), including: Henan, Luxi, Tulufan, Xishuangbanna and Zhangzhou, were sequenced using a DNA sequencing method. The results showed that there were six haplotpes found in the five game chicken breeds. The haplotype diversity ranged from 0.42857 to 0.78571, and the nucleotide diversity ranged from 0.00080 to 0.00654. The greatest genetic difference was between the Zhangzhou game and other game chickens. The analysis of the phylogenetic trees for the chickens constructed based on their haplotypes, indicated that the Chinese game chicken may originate from several subspecies of red jungle fowl. In conclusion, the genetic diversity of Chinese game chicken is not rich, and the maternal origin of Chinese game chicken may be from several subspecies of red jungle fowl.

Comparative analysis of codon usage and tRNA in mitochondrial genomes of Callus gallus.

Codon usage in mitochondrial genes of 11 Gallus gallus and two Anatidae species was analysed to determine the general patterns in codon choice of Callus gallus species. C3 contents were higher in Gallus gallus than in mammalian mitochondrial genomes that encode protein codon positions. The high C3 contents of Callus gallus might be the result of relatively strong mutational bias that occurred in the lineage of the Callus gallus species. A and C ending codons were detected as the “preferred 77 codons in Callus gallus and Anatidae. The NNR codon families are dominated by the A-ending codons, the NNY codon families are dominated by the C-ending codons and the NNN codon families are dominated by the A-ending or the C-ending codons. A comparison of the relative synonymous codon usage (RSCU) and synonymous codon families (SCF) of tRNA and proteins was made, and two groups can be classified by SCF. The codon usage in Callus gallus species indicates that codons containing A or C at the third position are used preferentially, regardless of whether corresponding tRNAs are encoded in the mtDNA. In both Callus gallus and Anatidae species mtDNA, codon usage biases are highly related to CC-ending binucleotide condons.