CRB: Methods of Genealogical and Genetic Analysis in Conservation Biology

从遗传学的角度来看，保护生物学需要保存遗传多样性或变异性。在很长一段时间内，突变提供了自然选择可能采取行动的遗传变异。然而，在大小受限于几代人的种群中，大部分遗传变异可能会丢失。一旦丢失，突变需要很长时间才能重新建立先前存在的遗传多样性水平。此外，许多物种现在受到极端和非自然选择的影响。因此，研究小种群遗传变异的维持具有重要的现实意义。近年来，小种群中的基因生存问题得到了很好的研究，新的统计方法已被应用于评估濒危物种小种群的遗传潜力，如安第斯秃鹰和普氏马匹。华盛顿大学的伊丽莎白·汤普森博士和她的同事们将在三个项目中扩展这项统计研究。对一个小种群的谱系结构的分析有三个方面，所有这些都与遗传管理直接相关，从而与物种的保护生物学有关。从系谱、遗传模型和观测数据这三个中心，人们可以考虑对系谱结构的推断，对观察到的性状的遗传基础的推断，或者对基因存活概率或特定表型事件的计算。目前提议的重点是在DNA指纹数据等复杂遗传数据的背景下，将以前的方法扩展到这三个领域并开发新的方法。了解种群的遗传和谱系结构是保护濒危物种的基础，在这种情况下，濒危物种以有限的数量或零散的孤立存在。仅靠对遗传学的研究并不能提供具体的解决方案。然而，所有物种都有基因，所有种群都有谱系，所有基因分离株的结构都会影响它们的维持和长期生存。

From a genetic perspective, conservation biology requires the preservation of genetic diversity or variability. Over long periods of time, mutation provides the genetic variation upon which natural selection may act. However, in populations constrained in size over several generations, much of the genetic variation may be lost. Once lost, a very long time is required for mutation to reestablish pre.existing levels of genetic diversity. Moreover, many species are now subject to extreme and unnatural selection. It is therefore of practical importance to study the maintenance of genetic variation in small populations. Questions of gene survival in small populations have been well studied in recent years, and new statistical methodology has found application in the assessment of the genetic potential of small populations of endangered species, such as the Andean condor and Przewalski's horse. This statistical research will be extended in three projects by Dr. Elizabeth Thompson and her colleagues at the University of Washington. There are three aspects of the analysis of the pedigree structure of a small population, all of which are directly relevant to the genetic management, and thence to the conservation biology of species. From the central trio of pedigree, genetic model, and observational data, one can consider inferences of pedigree structure, inferences of the genetic basis of an observed trait, or computation of probabilities of gene survival or of specific phenotypic events. The currently proposed focus is the extension of previous methods and development of new approaches to these three areas, in the context of complex genetic data such as DNA.fingerprint data. An understanding of the genetic and genealogical structure of populations is fundamental to conservation, where endangered species exist in limited numbers or fragmented isolates. A study of the genetics alone cannot provide specific solutions. However, all species have genes, all populations have pedigrees, and all genetic isolates have a structure that will affect their maintenance and long.term survival.