Deploying advanced data analytics, scientists at the New York Genome Center (NYGC) are uniquely harnessing a family-centric approach for identifying genetic variants that influence the risk of serious diseases such as Alzheimer’s disease, cardiac disease and diabetes.
The approach enables a broad study of these diseases because it utilizes the DNA from family members of patients to map risk factors, rather than the DNA from the patients themselves. The researchers refer to this methodology as genome-wide association studies by proxy. This allows genomic studies of diseases where it may be difficult to obtain DNA samples from patients themselves.
The innovative approach is described in a study recently published in Nature Genetics by Dr. Joseph Pickrell, Core Member and Assistant Professor, NYGC and Assistant Professor, Columbia University; Dr. Yaniv Erlich, Core Member and Assistant Investigator, NYGC, and Assistant Professor, Columbia University; and, Dr. Jimmy Liu, Bioinformatics Scientist at NYGC. The researchers illustrated the technique by performing genome-wide association studies by proxy on 12 common diseases in more than 100,000 individuals whose DNA data is housed at the UK Biobank — a database from a large population-based study of over 500,000 individuals ages 40-69 recruited from 2006 to 2010.
The authors combined these results with published summary statistics in what is known as a meta-analysis. The results predictably replicated established risk variants, and they also identified 17 newly associated variants — four in Alzheimer’s disease, eight in coronary heart disease and five in type 2 diabetes.
In the study “Case-control association mapping without cases,” the authors describe how this technique researchers to perform disease studies that were previously impossible. For example, large studies like the UK Biobank or the US Precision Medicine Initiative tend to recruit healthy individuals. There are few people with serious diseases like Alzheimer’s disease in these studies. Instead of relying on genomic analysis of patients themselves, the technique described by the NYGC researchers involves genotyping family members of patients.
Dr. Pickrell predicted that use of this approach could be an important tool for studying a broad range of diseases. “There are many diseases—from autism to sudden cardiac death to dementia — where recruiting patients into studies has historically been difficult or impossible,” said Dr. Pickrell. “Using this technique, we hope to run powerful genomic studies of these diseases.”
Dr. Erlich described the technique as, “Informing disease biology but also demonstrating the effectiveness of using family history of disease as an important ingredient in uncovering the variants that cause these ailments.”
To read the full study, click this link.