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G F LeBlond

Publications and source records attributed to G F LeBlond.

3 recordsLinked to original sources

Two-dimensional electrophoresis southern transfer method for detecting human genome variability using a LINE-1 sequence probe.

A "high-resolution, two-dimensional Southern transfer" method has been developed and was used to examine the distribution of a class of interspersed repeated sequences in human genomes. This method consists of two separate restriction enzyme digestions, including an in situ digestion, and two-dimensional electrophoresis using a large-sized agarose gel. The first 163-base-pair region of the human LINE-1 full-length sequence was used to probe human genomic DNA from placental tissue samples. About 900 LINE-1 signals were resolved from each DNA sample within a 2-D plane. The bulk of the fragments were between 0.5 to 23 kilobases in length. At a minimum 15 variant signals were detected between DNA samples from male and female individuals and at a minimum 16 variant signals were detected between two different female samples. This approach can potentially be used to perform high-resolution human genome fingerprinting analyses.

Base Sequence

Vatican error.

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Academies and Institutes

Discriminatory 32P 3'-end labeling of restriction endonuclease co-digested DNA fragments.

We present an improved method for selectively labeling specific DNA fragments in a mixture of restriction fragments. lambda DNA, used to develop the procedure, was digested with a combination of restriction enzymes and treated, at various incubation temperatures, with reverse transcriptase and one or more [alpha-32P]dNTP molecules. The labeled fragments were subjected to agarose gel electrophoresis and detected by autoradiography. We were able to direct the 3'-end labeling to precise subpopulations of DNA fragments, generated by multiple restriction enzyme digestions. We also show that labeling selectivity of DNA restriction fragments, by reverse transcriptase, is affected by the incubation temperature used during the labeling reaction. This paper describes an approach to 3'-end label select DNA fragments with reverse transcriptase and [alpha-32P]dNTPs. The procedure permits the bypassing of time-consuming isolation and purification steps required, by conventional radiolabeling techniques, to radiolabel specific DNA fragments.

Autoradiography