Major histocompatibility I gene diversity in the critically endangered Laysan duck (Anas laysanensis) / Philip Lavretsky, Andrew Engilis Jr., and Jeffrey L. Peters.

Includes bibliographical references (pages 92-93).

Quantifying the genetic composition of founder populations is important to the success of reintroduction programmes,
especially for bottlenecked and/or specialized species, such as island endemics. By implementing admixture schemes
based on genetic variability, captive breeding programmes can minimize the detrimental effects of bottlenecking,
inbreeding depression, outbreeding depression, etc. Particular attention has been given to genes within the major
histocompatibility complex (MHC) due to their direct correlation to an individual’s immunity. However, isolating and
amplifying MHC haplotypes remains difficult owing to the high diversity and paralogous nature. We describe a method
of MHC I haplotype isolation based on an iterative process of primer design for the endangered island endemic, the
Laysan duck (Anas laysanensis). Ultimately, haplotype-specific primers allow for direct genotyping after gel electrophoresis
based on the presence/absence of their respective amplicons. Using the developed techniques, a total of eight unique
haplotypes were isolated and assayed across 21 Laysan duck individuals from Laysan Island (N = 10) and Midway
Atoll (N = 11). The presence/absence of seven haplotypes were variable across individuals with three haplotypes present
in 95% of individuals, three in 38% of individuals, and one in 90% of individuals. The protocols described herein provide
a simple, cost-effective method for isolating haplotypes and monitoring existing MHC variation in Laysan ducks, and
the general approach can be applied to other molecular markers and species with low genetic diversity.