Researchers at Harvard Medical School and the Digital Biology Center at Bio-Rad Laboratories, Inc., have developed a rapid, scalable, and cost-effective method for chromosomal phasing that provides researchers with a new method to determine if genetic variants are linked on the same chromosome. Using Bio-Rad's Droplet Digital PCR (ddPCR(TM)) technology, the Drop-Phase method can rapidly determine the chromosomal phase of allelic markers hundreds of kilobases apart. This ability may provide new insights into the cause, penetrance, and severity of diseases. The collaborators published their findings online on March 4, 2015 in the open-access journal PLOS ONE in a research article titled "A Rapid Molecular Approach for Chromosomal Phasing." The "phase" (or linked arrangement) of variants along a single chromosome is known as the haplotype, which is an important piece of the genetic puzzle of a disease. Haplotype cannot be determined from standard DNA sequencing, due to short read lengths. Unlike conventional phasing methods that are tedious and expensive, Drop-Phase can be used to quickly and affordably determine the phase of multiple sequence variants in a region of interest after a sample has been sequenced. The resulting haplotype data can then be used to characterize how specific combinations of variants contribute to the severity of a disease. Drop-Phase can also be used to screen individuals for specific haplotypes when sequencing data are unavailable. This is particularly valuable for prospective clinical trials. "We expect researchers to use Drop-Phase to resolve the configuration of variants discovered from genome-wide association studies and determine whether certain haplotypes contribute to the severity of a disease," said Dr.Login Or Register To Read Full Story