Suitability of Some Data Quality Controls Thresholds for Genetic Association Studies of Admixed Population

Background: In genetic studies, the quality of DNA samples is tested first. Samples that are low-quality are not used. Some studies involve minority ethnic groups. And example is admixed African American. These studies often have small sample sizes. It is important to make sure samples are not discarded unnecessarily. This may happen by using quality control (QC) thresholds for homogenous groups. These may not be appropriate for an admixed group. Researchers want to study samples that failed certain QC tests. They want to see if this has to do with the ancestry of the outliers or the quality of the samples. Objectives: To study samples that fail heterozygosity and sample genotype call rate QC. To see if the failing rates have to do with the ancestry composition of the outliers or the quality of the samples. Eligibility: No new participants. Researchers will review data that has already been collected. Design: Researchers will study DNA samples in a lab. The samples will not include data that can identify the person the sample came from.