DNA sequences of swine leukocyte antigens (SLA) DRB exon 2 from five populations were used to investigate genetic polymorphism of black Dahe pig in Yunnan province of China. Our results showed that the SLA-DRB exon 2 of black Dahe pig obtained high variable rate of 23.50%, which was higher than the values analyzed for cattles or other livestocks. The average G + C content at the third synonymous variable coding positions (GC3) was closed to 0.78. The amino acids composition rate and majority of relative synonymous codon usage were near the ranges of 0.00 to 11.27 and 1.00 to 2.00, respectively. These significant polymorphism, high GC3 content and differentiation of preferred codon usage could be resulted from over dominance selection, base compositional bias and the diversity of gene expression level. Aforementioned results adequately testified the SLA-DRB exon 2 may be an important genetic marker for studies in genetic diversity, population genetics, breeding reproduction investigation and exploring new functional genes of black Dahe pig.
Figure. The correlation between codon frequency and relative synonymous codon usage. The above and below lines indicate the 95% confidence interval.
1. Author Information:Lizhou Tang, Long Yu1, Jiangang Chen, Junjie Wang, Mei Ma, Weidong Lu and Tongzuo Zhang
Correspondence: E-mail address: E-mail: luweidonghxx@yahoo.com.cn, zhangtz@nwipb.ac.cn. Tel: +86-874-8998627.
2. Published : African Journal of Biotechnology, 11(18), 4305-4310, 1 March, 2012