Dna Fragment Analysis And Genotyping Software

Fairly sophisticated software has been developed to take sample electrophoretic data rapidly through the genotyping process just described (Ziegle et al. 1992). For ABI 310 users (see Chapter 14), this is done in two steps by two different software programs. GeneScan® software is used to spectrally resolve the dye colors for each peak and to size the DNA fragments in each sample. The resulting electropherograms are then imported into the second software program, Genotyper®. This program determines each sample's genotype by comparing the sizes of alleles observed in a standard allelic ladder sample to those obtained at each locus tested in the DNA sample. As will be discussed in Chapter 17, Applied Biosystems also has a software package called GeneMapper ID that combines the functions of GeneScan and Genotyper with additional quality scores for the data.

Once GeneScan® processed electropherograms are imported into Genotyper®, a macro named 'Kazaam', that is specific for the STR loci and allelic ladders in each AmpFlSTR® kit, is initiated in Genotyper® to actually perform the allele calling. At this point, the analyst usually examines the peaks that have been called and based on their experience may or may not edit the calls made by the software. An allele table may then be created from the edited allele calls. Finally, the alleles may be exported to a spreadsheet program, such as Microsoft Excel, for further data analysis or uploading into a DNA database.

FMBIO II/III users (see Chapter 14) perform automatic band calling, quantify peak heights and areas, and determine DNA band sizes through comparison to size standards with the FMBIO® Analysis Software. The analyst adjusts the color separation to obtain the best resolution between the dye labels. Gel bands in each color are then manually edited in order to make allele calls. Automated genotype calling from FMBIO STR data is performed with STaR Call™ Genotyping Software. This software takes the calculated STR allele base pair sizes and converts each peak into the appropriate allele call based on the fragment's calculated size compared to the calculated sizes of the alleles in the allelic ladder. Allele 'look-up' tables in StaR Call™, which are basically

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Stammering Its Cause and Its Cure

Stammering Its Cause and Its Cure

This book discusses the futility of curing stammering by common means. It traces various attempts at curing stammering in the past and how wasteful these attempt were, until he discovered a simple program to cure it. The book presents the life of Benjamin Nathaniel Bogue and his struggles with the handicap. Bogue devotes a great deal of text to explain the handicap of stammering, its effects on the body and psychology of the sufferer, and its cure.

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