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The Formosan pangolin (Manis pentadactyla pentadactyla) is an endangered species in Taiwan. Usually, a decline in population size leads to a decrease in genetic diversity and increases the risk of extinction. Thus, measuring genetic diversity of Formosan pangolins in Taiwan is important in conservation programs. The major histocompatibility complex (MHC) genes play a crucial role in the immune response in many animals. Therefore, polymorphisms at these gene regions could provide an indicator for the immunological fitness of a population. In this study, seven different novel markers for MHC genotyping of Formosan pangolin were developed. In total, 92 Formosan pangolins from throughout Taiwan were collected and used to evaluate their genetic diversity. In the MHC markers, six loci showed monomorphism or only two haplotypes. Only one marker, a DLA class II DR-1 beta chain-like locus, showed more diversity: four haplotypes were detected and their relative frequencies were 62.0, 37.0, 0.5 and 0.5%, with nine polymorphic sites in the nucleotide sequence and six variable sites in the amino acid sequence. Moreover, the non-synonymous substitution rate (dN) and synonymous substitution rate (dS) were 0.026 and 0.017, and showed that this locus appears to be under positive selection (dN /dS >1). In the DLA class II DR-1 beta chain-like locus, the observed heterozygosity (HO) and expected heterozygosity (HE) were 0.413 and 0.482, respectively. FIS was 0.144, indicating that the population might have an inbreeding tendency (FIS > 0). Haplotype diversity (h) was 0.482 and nucleotide diversity (π) was 0.010. Overall, the present results indicate that the genetic diversity of MHC genes among Formosan pangolins in our sample population may be insufficient. |
