Sexual PCR

A perfect correlation would be indicated if all the points lay on a 45° line the actual results point towards sufficient correlation. The five best mutants in the broken-line circle were selected to be subjected to DNA recombination, the sexual PCR (Stemmer, 1994a). The method is depicted in Figure 11.9. Genes are pooled in the test tube and split with DNAse at random positions. After electrophoresis... 

Recombination is a powerful force in natural evolution it serves to propagate positive traits and eliminate negative traits in progeny. Stemmer has described a method for random gene recombination in vitro, which he calls DNA shuffling or sexual PCR [7.8], Initially, the DNA from a collection of enzyme variants to be shuffled is amplified by PCR. The resulting DNA is... 

The statistical mechanics approaches to genetic algorithm dynamics can be applied to the newly developed technique of sexual PCR, in which nucleotide sequences can be recombined at multiple sites [153,154],... 

The method of DNA shuffling, also known as sexual PCR, is the first and most widely used... 

This isoform was found as the result of a mouse deficient in the oxysterol 7a-hydroxylase gene (CYP7B1 in humans), which nonetheless did not accumulate 24-hydroxy cholesterol from the CYP46pathway, suggesting the existence of another 7ot-hydroxylase (Li-Hawkins et al., 2000). However, very httle evidence exists for its expression in human brain. Nishimura et al. quantified CYP39A1 mRNA by RT-RT-PCR and reported some 100-fold less than they reported for CYP51 mRNA (Nishimura et al., 2003). There is no other evidence for the expression of this isoform in the brain as of this writing and this is beheved to be the first report of its kind. The isoform has been shown to be sexually dimorphic in the liver (Li-Hawkins et al., 2000). 

Conventional forensic DNA analysis involves DNA extraction and purification, quantification, and amplification, followed by separation of PCR products, detection, and data analysis. In sexual assault casework, differential extraction, a cell sorting process by which DNA is differentially extracted from sperm and vaginal epithelial cells (or other nonsperm cell types), must be utilized to obtain enriched fractions of male and female DNA. In this chapter, we will discuss the specific development of these techniques on the microscale for application to forensic human DNA analysis. 

The animal origin of the meat can be determined by immunochemical and/or electrophoretic methods of analysis as well as by PCR. The PCR method is described in 2.6.4.2.2. Electrophoretic protein analysis will be discussed here. The sexual origin of a meat sample can also be of interest, as discussed here for beef. 

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