RESUMO
We propose a CRISPR/Cas12a-mediated recombinase polymerase amplification (RPA) detection method that combines RPA with Cas12a cleavage for the detection of halal food adulteration, which is of global concern, particularly for Muslim consumers. We optimized the reagent concentrations for the Cas12a cleavage steps and designed and screened gRNA targeting a conserved area of the mitochondrial cytochrome C oxidase subunit I (COX1) gene. This procedure successfully detected the presence of porcine components as low as 5 pg/µL in the linear range of 5-1000 pg/µL. The assay's detection limit was 500 times lower than CRISPR-based approaches that exclude a preamplification step, allowing the detection of trace porcine DNA in food samples. The assay additionally showed no cross-reaction with nontarget species. Therefore, this detection platform shows tremendous potential as a method for the quick, sensitive, and specific detection of porcine-derived components.
RESUMO
BACKGROUND: Disruption of the cholinergic neurotransmitter pathway which is important for cognition, memory and learning abilities has been reported in Alzheimer's Disease (AD) patients. The receptors involved include the Cholinergic Receptors Muscarinic (CHRM). CHRM2 gene has been associated with intelligence, personality traits, substance dependence and depression. CHRM3 has been found to heterodimerize with CHRM2. METHODS: DNA samples from 240 AD patients with SNPs rs6962027 of CHRM2 gene and rs7511970 of CHRM3 gene were amplified using PCR and genotyped using Restriction Fragment Length Polymorphism (RFLP). Chi-squared test was done to check if the genes are in Hardy-Weinberg equilibrium. RESULTS AND CONCLUSION: Although the results did not show significant associations, these data denote plausible interaction between TT in SNP rs6962027 in CHRM2 gene and TT in SNP rs7511970 in CHRM3 gene affecting AD risk. SNP rs7511970 of CHRM3 gene may also exert an influence on late-onset AD.