Center for Human Identification, Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, USA.
Institute of Environmental Science and Research Limited, Private Bag 92021, Auckland, 1142 New Zealand.
Forensic Sci Int Genet. 2019 Jan;38:219-224. doi: 10.1016/j.fsigen.2018.11.009. Epub 2018 Nov 11.
The interpretation of mixed profiles from DNA evidentiary material is one of the more challenging duties of the forensic scientist. Traditionally, analysts have used a "binary" approach to interpretation where inferred genotypes are either included or excluded from the mixture using a stochastic threshold and other biological parameters such as heterozygote balance, mixture ratio, and stutter ratios. As the sensitivity of STR multiplexes and capillary electrophoresis instrumentation improved over the past 25 years, coupled with the change in the type of evidence being submitted for analysis (from high quality and quantity (often single-source) stains to low quality and quantity (often mixed) "touch" samples), the complexity of DNA profile interpretation has equally increased. This review provides a historical perspective on the movement from binary methods of interpretation to probabilistic methods of interpretation. We describe the two approaches to probabilistic genotyping (semi-continuous and fully continuous) and address issues such as validation and court acceptance. Areas of future needs for probabilistic software are discussed.
从 DNA 证据材料中解读混合谱型是法医科学家面临的更具挑战性的任务之一。传统上，分析人员采用“二进制”的解释方法，使用随机阈值和其他生物学参数（如杂合子平衡、混合比和 stutter 比）来推断基因型，要么包含在混合物中，要么排除在混合物之外。随着过去 25 年来 STR 多重扩增和毛细管电泳仪器的灵敏度的提高，再加上提交分析的证据类型的变化（从高质量和数量（通常是单源）的污渍到低质量和数量（通常是混合）的“接触”样本），DNA 谱型解读的复杂性同样增加了。本综述提供了从二进制解释方法到概率解释方法的历史视角。我们描述了两种概率基因分型方法（半连续和完全连续），并讨论了验证和法庭接受等问题。讨论了概率软件未来的需求领域。
