National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20894, USA.
BMC Med Genet. 2010 May 2;11:68. doi: 10.1186/1471-2350-11-68.
Because they are a closed founder population, the Old Order Amish (OOA) of Lancaster County have been the subject of many medical genetics studies. We constructed four versions of Anabaptist Genealogy Database (AGDB) using three sources of genealogies and multiple updates. In addition, we developed PedHunter, a suite of query software that can solve pedigree-related problems automatically and systematically.
We report on how we have used new features in PedHunter to quantify the number and expected genetic contribution of founders to the OOA. The queries and utility of PedHunter programs are illustrated by examples using AGDB in this paper. For example, we calculated the number of founders expected to be contributing genetic material to the present-day living OOA and estimated the mean relative founder representation for each founder. New features in PedHunter also include pedigree trimming and pedigree renumbering, which should prove useful for studying large pedigrees.
With PedHunter version 2.0 querying AGDB version 4.0, we identified 34,160 presumed living OOA individuals and connected them into a 14-generation pedigree descending from 554 founders (332 females and 222 males) after trimming. From the analysis of cumulative mean relative founder representation, 128 founders (78 females and 50 males) accounted for over 95% of the mean relative founder contribution among living OOA descendants.
DISCUSSION/CONCLUSIONS: The OOA are a closed founder population in which a modest number of founders account for the genetic variation present in the current OOA population. Improvements to the PedHunter software will be useful in future studies of both the OOA and other populations with large and computerized genealogies.
由于 Lancaster County 的 Old Order Amish（OOA）是一个封闭的奠基人群体，因此他们成为了许多医学遗传学研究的对象。我们使用三种来源的族谱并进行多次更新，构建了四个版本的 Anabaptist Genealogy Database（AGDB）。此外，我们还开发了 PedHunter，这是一套查询软件，可以自动、系统地解决系谱相关问题。
我们报告了如何使用 PedHunter 的新功能来量化奠基人群体对 OOA 的数量和预期遗传贡献。本文通过使用 AGDB 中的示例，说明了查询和 PedHunter 程序的实用性。例如，我们计算了预计对当今现存 OOA 有遗传物质贡献的奠基人数，并估计了每个奠基人的平均相对奠基人代表。PedHunter 的新功能还包括系谱修剪和系谱编号重排，这对于研究大型系谱应该很有用。
使用 PedHunter 版本 2.0 查询 AGDB 版本 4.0，我们识别出了 34160 名假定的现存 OOA 个体，并在修剪后将他们连接成一个 14 代的族谱，该族谱源自 554 名奠基者（332 名女性和 222 名男性）。通过分析累积平均相对奠基人代表，在现存 OOA 后代中，有 128 名奠基者（78 名女性和 50 名男性）占了超过 95%的平均相对奠基人贡献。
讨论/结论：OOA 是一个封闭的奠基人群体，其中少数奠基者就代表了当前 OOA 群体中的遗传变异。PedHunter 软件的改进将有助于未来对 OOA 以及其他具有大型和计算机化族谱的群体的研究。
