Visible Genetics Inc.

Bayer Healthcare LLC

Henryk Zaleski

Alexandre M Izmailov

Paul Waterhouse

John A Renfrew

John K Stevens

James M Dunn

James Leushner

James W Cassidy

Eric Steinbach

Stephen Darasch

In order to align DNA sequence data traces, an experimental data trace representing the positions of a first species of base within a target polynucleotide and a reference data trace representing the positions of a second species of base (which may be the same as or different from the first species) within a reference polynucleotide are obtained by separating appropriate sequencing fragments generated from the target and reference polynucleotides on an electrophoresis gel. For each reference data trace, a plurality of peaks corresponding to fragments having a size in the range of 40 to 1200 bases are selected. A base number is assigned to each of the selected peaks in the reference data trace, and a numerical &ldquo;peak file&rdquo; is created with information about the peak number and migration time (or distance). This peak file is analyzed to determine a set of polynomial coefficients which will allow substantial linearization of a plot of peak number versus separation between adjacent peaks and alignment of the traces with respect to each other. These coefficients are used to create a corrected time scale identifying where peaks should be located on a given experimental gel. This corrected time scale is used to guide the sampling of the experimental data, and for assignment of peaks within the data.

Method for alignment of DNA sequences with enhanced accuracy and read length

Electrophoresis gels and gel holders having fiber spacers and method of

A high dynamic range apparatus for separation and detection of polynucleotide fragments has a housing adapted to receive an electrophoresis gel holder containing an electrophoresis gel loaded with fluorophore-labeled samples; one or more laser diodes for providing radiation of a frequency suitable for excitation of the fluorophore which irradiates a an array of excitation/detection sites on the electrophoresis gel; an array of detectors aligned with the excitation/detection sites for collecting fluorescent emissions; and one or more components for increasing the dynamic range of the instrument by at least an order of magnitude. These components, which can be used individually or in combination include detectors that are connected to a signal processing system that modulates the period of signal integration employed so that large signals are totaled at short time intervals and smaller signals are totaled at longer time intervals; the use of a beam splitter to produces a high intensity beam of emitted light and a low intensity beam of emitted light from each excitation/detection site; and a device for modulating the intensity of the excitation beam can be used to improve the dynamic range of the instrument.

High dynamic range apparatus for separation and detection of

Apparatus for preparing gels for use in electrophoretic separations and

An apparatus and method for thermally cycling a reaction mixture in a reaction vessel to expose the mixture to the varying temperatures necessary to, for example, achieve PCR amplification or the preparation of sequencing fragments using a cycle sequencing operation makes use of flow-through reaction vessels, such as capillary tubes, for the preparation and thermal cycling of reaction mixtures. In order to prevent loss of the reaction mixture from the vessels during heating, the thermal cycling apparatus of the invention provides means for sealing the proximal and distal end of each reaction vessel. The proximal ends can be sealed by coupling to a pump which permits movement of the samples within the reaction vessels. As to the distal ends, the reaction vessels can be sealed by pressing the distal end of each vessel against a sealing element with a conformable surface, or by immersing the distal end of each vessel in the reservoir of liquid, preferably of an oil, that is not miscible with the reaction mixture.

Method and apparatus for thermal cycling and for automated sample

Microgels for use in medical diagnosis and methods of making and using

Gel holders for electrophoresis gels are made using clad fibers, particularly glass fibers as spacers between substrates. A plurality of fibers with an high-melting interior core and a low-melting external cladding are placed between a first planar substrate and a second planar substrate. The fibers are heated to a temperature sufficient to at least soften the exterior cladding of the fibers without softening the interior core of the fibers, and then cooled while they are in contact with the first and second substrates to resolidify the exterior cladding. This adheres the fibers to the first and second substrates, and forms a gel chamber between said first and second substrates. The gel chamber has a thickness defined by interior core of the fibers. The fibers may be heated before or after the second substrate is placed over the top of the fibers. The gel holders thus formed may be filled immediately with a gel forming solution such as a polyacrylamide, or they may be stored indefinitely and used as needed.

Gel holders for electrophoresis gels are made using fibers, particularly glass fibers, which are affixed to the substrates forming the gel holder using an adhesive. These gel holders can be made by placing a plurality of adhesive-coated fibers between a first planar substrate and a second planar substrate; and applying pressure to the outside of the substrates to adhere the fibers to the first and second substrates. This forms a gel chamber between the first and second substrates which has a thickness defined by diameter of the fibers. Alternatively, uncoated fibers may be laid down in pairs, with a line of adhesive disposed between each fiber of the pair. When the adhesive is cured, it binds the fibers in position as spacers. At the same time, the fibers isolate the adhesive from the gel compartment. In this way, interference of components of the adhesive with the polymerization of the a gel in the gel chamber can be avoided. Gel holders formed using either of these methods may be filled immediately with a gel forming solution such as a polyacrylamide, or they may be stored indefinitely and used as needed.

Growing community of inventors

Niagara Falls, Canada

Henryk Zaleski