Artículos con la etiqueta ‘ADN’

Information Theory of DNA Sequencing

Por • 4 abr, 2012 • Category: Ciencia y tecnología

DNA sequencing is the basic workhorse of modern day biology and medicine. Shotgun sequencing is the dominant technique used: many randomly located short fragments called reads are extracted from the DNA sequence, and these reads are assembled to reconstruct the original sequence. A basic question is: given a sequencing technology and the statistics of the DNA sequence, what is the minimum number of reads required for reliable reconstruction? This number provides a fundamental limit to the performance of any assembly algorithm. By drawing an analogy between the DNA sequencing problem and the classic communication problem, we formulate this question in terms of an information theoretic notion of sequencing capacity. This is the asymptotic ratio of the length of the DNA sequence to the minimum number of reads required to reconstruct it reliably. We compute the sequencing capacity explicitly for a simple statistical model of the DNA sequence and the read process. Using this framework, we also study the impact of noise in the read process on the sequencing capacity.

Scientists Identify DNA That May Contribute to Each Person’s Uniqueness

Por • 20 ago, 2010 • Category: Ciencia y tecnología

Building on a tool that they developed in yeast four years ago, researchers at the Johns Hopkins University School of Medicine scanned the human genome and discovered what they believe is the reason people have such a variety of physical traits and disease risks.