RESUMEN
ABSTRACT: The increasing development of DNA sequencing and genotyping technologies has made possible to analyze the genomes of several species. Genomic studies of production animals have greatly increased the understanding of mechanisms that control the interactions of genetic and environmental factors involved in the expression of traits of economic importance. Several technologies have been presented by different companies for the genotyping of low-density SNP panels, which may be used in different applications with different goals, such as paternity testing, diagnosis of genetic diseases, and identification of genetically superior animals based on polymorphisms characterized in candidate genes. The present review critically analyzes the GoldenGate Beadxpress technology and puts its use in these applications into perspective.
RESUMO: A crescente evolução das tecnologias de sequenciamento e genotipagem de DNA tornaram possível analisar o genoma de várias espécies, compreender suas funções dentro dos sistemas biológicos e, sobretudo, começar a entender os mecanismos que controlam as interações entre os genótipos e os efeitos ambientais que estão envolvidos com a expressão de características de interesse econômico. Várias tecnologias foram apresentadas por diferentes empresas para a genotipagem de painéis de SNP de baixa densidade, os quais podem ser utilizados em diferentes aplicações com objetivos variados, desde testes de paternidade e diagnósticos de doenças genéticas até a identificação de animais geneticamente superiores, com base em polimorfismos caracterizados em genes candidatos. Essa revisão analisa a tecnologia Goldengate Beadxpress e coloca em perspectiva seu uso nessas aplicações.
RESUMEN
The high oleic (C18:1) phenotype in peanuts has been previously demonstrated to result from a homozygous recessive genotype (ol1ol1ol2ol2) in two homeologous fatty acid desaturase genes (FAD2A and FAD2B) with two key SNPs. These mutant SNPs, specifically G448A in FAD2A and 442insA in FAD2B, significantly limit the normal function of the desaturase enzyme activity which converts oleic acid into linoleic acid by the addition of a second double bond in the hydrocarbon chain. Previously, a genotyping assay was developed to detect wild type and mutant alleles in FAD2B. A real-time PCR assay has now been developed to detect wild type and mutant alleles (G448A) in FAD2A using either seed or leaf tissue. This assay was demonstrated to be applicable for the detection of homozygous and heterozygous samples. The FAD2A genotyping assay was validated by employing gas chromatography (GC) to determine total fatty acid composition and by genotyping peanut lines that have been well characterized. Overall, development of rapid assays such as real-time PCR which can identify key genotypes associated with important agronomic traits such as oleic acid, will improve breeding efficiency by targeting desirable genotypes at early stages of development.
Asunto(s)
Ácido Graso Desaturasas/análisis , Ácido Graso Desaturasas/química , Arachis/genética , Arachis/química , Cromatografía de Gases/métodos , Reacción en Cadena de la Polimerasa/métodosRESUMEN
Molecular genetic research relies heavily on the ability to detect polymorphisms in DNA. Single nucleotide polymorphisms (SNPs) are the most frequent form of DNA variation in the genome. In combination with a PCR assay, the corresponding SNP can be analyzed as a derived cleaved amplified polymorphic sequence (dCAPS) marker. The dCAPS method exploits the well-known specificity of a restriction endonuclease for its recognition site and can be used to virtually detect any SNP. Here, we describe the use of the dCAPS method for detecting single-nucleotide changes by means of a barley EST, CK569932, PCR-based marker.
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Hordeum/genética , Polimorfismo de Nucleótido Simple , Enzimas de Restricción del ADN , Genoma , Reacción en Cadena de la PolimerasaRESUMEN
There is an increasing interest in single nucleotide polymorphism (SNP) typing in the forensic field.SNPs are very useful for deftning Y chromosome or mtDNA haplotypes and DNA phenotyping.We focus on comparative advantages of SNP typing over length variations and expected number of loci required to gain probabilities equal to sTR loci in use.This review also offers to the reader a state of the art of SNP genotyping technologies with the advantages and disadvantages of the different techniques and platforms for different forensic requirements.