Familias stands as a robust, free software solution meticulously designed for complex probability calculations in DNA-based paternity and relationship inference. For those seeking the latest version and supplementary resources, please visit our dedicated Download section.
The Familias program is expertly engineered to navigate scenarios where DNA profiles are available, yet familial relationships remain uncertain. Expanding upon the capabilities of its predecessor, pater, Familias distinguishes itself by adeptly managing multiple alternative pedigrees simultaneously. When presented with various potential family trees or pedigrees for a group, alongside DNA measurements from select individuals and a comprehensive database of DNA observations pertinent to the population, Familias excels at determining the most probable pedigree and quantifying its likelihood compared to others. While similar programs exist, Familias’s hallmark is its proficiency in handling intricate cases. This includes scenarios where potential mutations are factored in and the simultaneous evaluation of multiple pedigrees is required. It’s important to note that Familias is not designed for computations involving linked markers; for such analyses, we recommend FamLink.
Background and Development of Familias
The genesis of Familias software, and its earlier iteration pater, is rooted in a collaborative effort between Petter Mostad and Thore Egeland, then affiliated with the Norwegian Computing Center, and Bjørnar Olaisen, Margurethe Stenersen, and Bente Mevåg from the Institute of Forensic Medicine (RMI) in Oslo. The Norwegian Computing Center, a non-profit institution dedicated to applied research, provided the institutional framework for this development. The partnership with RMI commenced in 1994, culminating in the initial software release in 1995. Continuous enhancements have been implemented since, with the most recent update in May 2010. The ongoing development and refinement of Familias are now under the stewardship of Daniel Kling at the Department of Forensic Sciences, Oslo University Hospital, ensuring its continued relevance and efficacy in the field.
Methodological Approach of Familias
The application of Familias software extends to even the most fundamental cases, such as paternity disputes. In such instances, the objective is to ascertain whether a particular man is the biological father of a child. Typically, this involves analyzing DNA data from the child, the mother, and the alleged father. Crucially, population-specific databases detailing allele frequencies are also necessary for accurate calculations. Utilizing this data, Familias computes the likelihood odds of the putative father being the true biological father. In essence, paternity cases are evaluated by contrasting two primary hypotheses or pedigrees: one where the man is the father, and another where he is not. Familias’s strength lies in its capacity to calculate odds for any pair of alternative pedigrees, extending beyond simple paternity tests to determine relationships such as uncle-nephew, sister-sister, and more complex familial connections. Furthermore, Familias is capable of simultaneously assessing multiple competing hypotheses, offering a comprehensive approach to relationship testing.
In contemporary human DNA typing systems, mutations are a recognized phenomenon. Failure to account for potential mutations can lead to erroneous exclusions of correct pedigrees. Familias software incorporates a sophisticated mechanism to weigh the probability of mutations against other genetic evidence, thereby enhancing the accuracy of relationship assessments, especially in complex familial scenarios.
Familias also encompasses a suite of additional features, including adjustments for kinship, further expanding its utility in diverse forensic and genetic contexts. Comprehensive details are available in the Documentation.
Utilizing Familias in Practice
To begin using Familias, the software is readily available for download. We provide a concise tutorial and a detailed manual to facilitate user adoption. Designed for Windows operating systems, Familias is specifically tailored for practical application within DNA testing laboratories. It represents the culmination of extensive and continuous development, making it a reliable tool for professionals in the field.
For researchers, the core functionalities of Familias have been integrated into an R package, named OpenFamilias, broadening its accessibility and application in research settings. Further information can be found on the OpenFamilias pages.
For any inquiries or support needs, please consult our Help section or reach out to Daniel Kling directly.
Citing Familias in Publications
When referencing Familias in academic or professional publications, please cite the following key articles:
Additional References for Further Reading
Egeland, Thore; Mostad, Petter: “Statistical Genetics and Genetical Statistics: a Forensic Perspective”. Scand. Journal of Statistics, Vol 29, 2002.