DNA Fingerprinting and its Application to Aviculture: Nice to Know, For the Birds, or Critical?

Abstract

T Introduction

he article is ahout aviculture and genetics ..... Wait! Please don't go to the next article just yet. I promise to skip all the introductory esoteric, coma-inducing mumbo-jumbo about DNA that we scientists feel compelled to describe so you can properly understand 1) how DNA works, and 2) how it can he assayed to provide an immutable mark or fingerprint for individual hirds. These fingerprints can he used to determine the relatedness of pairs or potential pairs, to improve hreeding success, and to establish geneticallyviahle aviary collections for the longterm. While we don't all need to he geneticists to use the results, I think most would agree that we do need to have the fingerprint technology in order to achieve long-term success in aviculture. Also, the availability of DNA fingerprints will remove the foremost impediment (no foolproof marking system) presently restricting free, or nearly-free, international trade in legitimate captive-bred birds.

The DNA technology for achieving the stated avicultural goals, in fact, already exists for all birds, hut the process is slow, labor intensive, and therefore, expensive. The present high cost and the fact that there are so few laboratories which offer this service has resulted in the approach being impractical, albeit technically feasible. Recognition of the need for DNA fingerprinting in aviculture, led me as 1) Director of Conservation for the American Federation of Aviculture, and 2) as President of a private-sector research genetics company (LGL Ecological Genetics, Inc.) to apply to the National Science Foundation for a Small Business Innovative Research (SBIR) grant to develop the needed technology.

We were awarded a Phase I grant (Award DMI-9461111, effective 1 January 1995) that allowed us six (6) months to conduct preliminary

research towards development of the needed technology. Depending on a successful outcome of a scientific peer-review of our Phase I research results, we would be able to compete on a national basis for the limited funds available from the National Science Foundation to support larger Phase II awards. We completed our Phase I research on schedule, and based upon the results of scientific peer reviews of our Phase I report and Phase II research proposal, we were awarded a 2-yr Phase II grant on 15 July 1996 (Award DMI-9529743).

In our Phase I study we developed the technology enabling automated DNA profiling of the Hyacinth Macaw (Anodorhynchus hyacinthinus) and demonstrated that the method could identify individuals and their progeny with certainty, as well as establish the degree of relatedness among individuals. We also demonstrated that the method developed for this single species of macaw appeared to extend to other species of macaws, as well as to other groups of psittacines, at least in part. In our Phase II research we will develop the technology for all the major groups of psittacine birds involved in international trade and domestic aviculture.

Below, I provide a background on DNA profiling (fingerprinting), outline the approach we are using, summarize the results of our Phase I research, and describe the research plan for extending our technology to other groups of exotic birds. It should also be noted that we (Gallaway et al. 1995) have previously used the same approach to develop DNA fingerprinting protocols for the Emu (Dromaius novaehollandiae). In that study, we were able to demonstrate that the degree of relatedness was correlated with production attributes, and showed that genetic-based pairings of captive stock could markedly improve production and stabilize the captive gene pool.

Background

All you have to know for now is that DNA contains "genes" which are located at specific places on the DNA strands which are found in the nucleus of every cell in the body. These places are referred to as loci (plural for "locus," a specific address on the DNA molecule). At each locus, a gene has two elements (called alleles); one of which was donated by mom and one from pop. These alleles often have many forms in the overall population, and may govern things such as eye color, hair color, length of the big toe, etc. While there can be many alleles in the population as a whole, an individual is restricted to only two, one from mom and one from pop.

Some of the alleles, say for brown eyes, dominate others, say for blue eyes. If pop gave you his allele for brown eyes and mom gave you her allele for blue eyes, you are going to have brown eyes. Period. You, however, carry (and can pass along to your offspring) the allele for blue eyes. You are said to be "heterozygous" (with two different alleles) at that gene (locus). If both your eye color alleles had been for brown eyes you would be said to be "homozygous" (the two alleles are the same) at that gene.

For you to have the recessive trait of blue eyes both of your parents would have to have carried the allele for blue eyes. Tims, don't worry too much if your parents both have brown eyes and you ended up having blue eyes. They were both heterozygous at the eye color locus and each donated you the allele for blue eyes (you are homozygous). However, if both your parents have blue eyes and you have brown eyes, it might be time for a family chat.

Now, lets think about the population. There are brown eyes, black eyes, green eyes, blue eyes, hazel eyes and on and on. However, some colors are more prevalent than others; i.e., brown eyes are more frequently seen than blue eyes (I think), black eyes are more common than green eyes, etc. Sometimes even a very rare color can he observed (say red). If you have one of these rare alleles, it can provide a marker showing you to be (outside of your immediate family) genetically distinct from most of the population.