DNA/RNA EXTRACTION

DNA/RNA extraction

DNA/RNA extraction

Part 1

Article Review

The article under review is “Manipulation of Molecular Processes with DNA Molecular Springs” by Diss.Wang, Andrew, published in “Arthritis Care & Research: American College of Rheumatology” in 2010.

Renin is the main rate-limiting enzyme in the renin-angiotensin-aldosterone system. Its gene, REN, is a candidate crucial factor in essential hypertension and cardiovascular disease. The aim of this study was to evaluate allele and haplotype distributions of REN polymorphisms, and to estimate normalised linkage disequilibrium (D') in Mexican and German populations. Four groups were studied for the REN single nucleotide polymorphisms (SNPs) 1205C>T, 1303G>A, and 10607G>A, in population samples of Mexican Mestizo (n = 86), Mexican Huichol (n = 49), German (n = 39), and individuals with hypertension diagnosis (n = 66).

Polymorphisms were detected by PCR-RFLP. Genotype, allele and haplotype frequencies were estimated. SNP 1205C>T and 10607G>A allele and genotype distribution showed inter-group differences. The 1205T and 10607A allele showed a significance difference in hypertensive population.

Haplotype analysis also showed some inter-group differences, especially in 1205C-1303G-10607G, 1205C-1303G-10607A and 1205T-1303G-10607G haplotypes. The segregation analysis disclosed complete linkage disequilibrium between 1205 and 1303 loci. These results provide an example of genetic diversity in related populations and illustrate the convenience of increasing the number of loci in associative studies between diseases and candidate genes.

Part 2

Identification are the most important tests used in crime labs today. STR methods include genotyping of the autosomal (nonsex chromosome) and Y chromosome STR loci. Mitochondrial DNA analysis is more labor intensive and less informative than nuclear STR techniques, but it can be very useful in providing information that we could not obtain otherwise. This entry deals with the interpretation of autosomal STR typing results and the CODIS database (Birx, 2001, 54).

A number of multiplex STR test kits are available for human identification. Multiplexing allows the analyst to amplify and genotype a number of genetic loci simultaneously, thereby conserving evidence and providing a great deal of information about the source of the sample under study. Many laboratories use a combination of two commercial kits known as AmpFlSTR CofilerTM and AmpFlSTR Profiler PlusTM; others use a single multiplex kit known as AmpFlSTR IdentifilerTM to achieve the same goal. The former test kits include the reagents to analyze 13 STR loci plus amelogenin. The latter kit allows for the analysis of 15 STR loci plus amelogenin. All three kits are manufactured by Applied Biosystems Inc. (ABI).

Other forensic DNA testing laboratories use multiplex kits manufactured by Promega Corp., including the GenePrint PowerPlex® 1.1 (8 loci), GenePrint PowerPlex® 2.1 (9 loci), and the PowerPlex® 16 System. Regardless of which test kits a laboratory uses, it is important that all 13 CODIS loci be included in the testing.

CODIS Database

CODIS refers to the Combined DNA Indexing System database that the FBI established as a pilot project in 1990. In 1994, Congress passed the DNA Identification Act, which formalized the authority of the FBI to establish this national database. CODIS consists of a national database (NDIS), state databases (SDIS), and local ...