A 50-SNP assay for biogeographic ancestry and phenotype prediction in the U.S. population.

When an STR DNA profile obtained from crime scene evidence does not match identified suspects or profiles from available databases, further DNA analyses targeted at inferring the possible ancestral origin and phenotypic characteristics of the perpetrator could yield valuable information. Single Nucleotide Polymorphisms (SNPs), the most common form of genetic polymorphisms, have alleles associated with specific populations and/or correlated to physical characteristics. We have used single base primer extension (SBE) technology to develop a 50 SNP assay (composed of three multiplexes) designed to predict ancestry among the primary U.S. populations (African American, East Asian, European American, and Hispanic American/Native American), as well as pigmentation phenotype (eye, hair, and skin color) among European American. We have optimized this assay to a sensitivity level comparable to current forensic DNA analyses, and shown robust performance on forensic-type samples. In addition, we developed a prediction model for ancestry in the U.S. population, based on the random match probability and likelihood ratio formulas already used in forensic laboratories. Lastly, we evaluated the biogeographic ancestry prediction model using a test set, and we evaluated an existing model for eye color with our U.S. sample set. Using these models with recommended thresholds, the 50 SNP assay provided accurate ancestry information in 98.6% of the test set samples, and provided accurate eye color information in 61% of the European samples tested (25% were inconclusive and 14% were incorrect). This method, which uses equipment already available in forensic DNA laboratories, is recommended for use in U.S. forensic casework to provide additional information about the donor of a DNA sample when the STR profile has not been linked to an individual.

A pilot study of the impact of a grief camp for children.

OBJECTIVE: Research indicates that children benefit from supportive interventions to help them cope with the loss of a loved one. The aim of this pilot study was to evaluate children's perceptions of the effectiveness of a grief camp. METHODS: Semistructured interviews were performed with 18 children who attended a weekend-long grief camp. Children also responded to follow-up interviews via telephone. Their parents also completed surveys before camp began and either after camp ended or at a follow-up evaluation. Data were analyzed using descriptive statistics and content coding to uncover key themes in the interviews. RESULTS: Children reported that art activities helped them to express feelings about their grief and release feelings of sadness and worry related to the death. Parents and children felt that the camp was a positive experience and that the children benefited from being in groups with peers who had also lost family members. SIGNIFICANCE OF RESULTS: Evaluating the impact of grief camps, using practical methods such as the ones for this study, is important, as these camps are becoming more popular interventions. Children and parents may benefit from contact at specified follow-up periods after camp to determine if they would benefit from further therapy. Results also provide evidence of the success of this program, which supports the need for funding these types of interventions.