Recombinant Brachyteles hypoxanthus Cytochrome c oxidase subunit 2 (MT-CO2)

Genetic Diversity

Genetic diversity studies utilizing MT-CO2 sequences provide critical insights into the conservation of Brachyteles hypoxanthus . These studies often involve analyzing haplotype diversity (h) and nucleotide diversity (π) to understand the genetic structure of different populations .

• Haplotype Diversity (h): Measures the uniqueness of haplotypes within a population .

• Nucleotide Diversity (π): Measures the average number of nucleotide differences between any two DNA sequences in a population .

Research indicates that Brachyteles hypoxanthus has comparatively low mtDNA variation compared to other neotropical primates . For example, a study comparing the HVSI sequences of Alouatta caraya (howler monkey) to those of Brachyteles hypoxanthus found 31 haplotypes in A. caraya samples, whereas B. hypoxanthus showed lower nucleotide diversity .

Research Findings

Several studies have employed MT-CO2 to investigate the genetic diversity and population history of Brachyteles hypoxanthus . Key findings include:

• Low Genetic Diversity: Brachyteles hypoxanthus exhibits low HVSI diversity compared to other threatened primates .

• Population Structure: Genetic diversity is scattered across remnant populations, with some less-protected populations retaining significant variation .

• Conservation Implications: Certain populations (PERD, PESB, RPPN-FMA, and SMJ) are identified as discrete management units due to their significant contribution to the species' genetic diversity .

2.1. Methods of Analysis

1. Sequencing and Alignment:

   • Sequences are aligned using CLUSTAL W and inspected in BIOEDIT 7.0.5.3 .

   • A BLAST search confirms the absence of exogenous DNA contamination .

   • The B. hypoxanthus sequence from GenBank (AF213966) is used as a reference for alignment and haplotype determination .

2. Software and Tools:

   • ARLEQUIN 3.01 is used for haplotype determination and population comparisons .

   • jMODELTEST is used to select the most appropriate nucleotide substitution model using the Akaike Information Criterion (AIC) .

   • DIYABC 1.0.4.38beta is used for Approximate Bayesian Computation (ABC) to test alternative scenarios for population diversification .

   • BEAST is employed to estimate parameters such as substitution rates using Bayesian methods .

   • LAMARC and MIGRATE-N 3.2.1 are used to estimate the mutation-scaled effective population size (θ) with coalescent-based methods .

2.2. Genetic Variability Estimates

Genetic variability is estimated using haplotype diversity ($h$) and nucleotide diversity ($\pi$) . The most appropriate model of nucleotide substitution is selected in jMODELTEST with the Akaike Information Criterion (HKY+I, base frequencies A = 0.3721, C = 0.2469, G = 0.1286, T = 0.2524, proportion of invariable sites of 0.9017, and transition/transversion ratio of 33) .

Conservation Implications

The genetic data obtained from MT-CO2 analysis has significant implications for the conservation management of Brachyteles hypoxanthus . Because population sizes are below accepted minimum viable population sizes, active management is required . Translocation of females between fragments is underway in some populations to reduce inbreeding effects .

Data Tables

Genetic diversity indices for Brachyteles hypoxanthus and other primate species:

4.1. Management Units

Populations suggested as discrete management units :

• PERD

• PESB

• RPPN-FMA

• SMJ