Question

i need help,please

Describe different karyotyping techniques (e.g. FISH) that can detect chromosome abnormalities and molecular techniques for genetic testing

Provide examples of why pharmacogenomics can change how many genetic disease conditions may be treated in the future .Define WGS and WES.

Review the terms RFLP, Microarrays, SNP’s, monoclonals and the role each plays in disease detection.

Answer 1

Diffewrent techniques to detect choromosomal abnormalities are

i) FISH- Fluorescence in situ hybridization is a molecular cytogenetic technique that uses fluorescent probes that bind to only those parts of a nucleic acid sequence with a high degree of sequence complementarity. FISH can be applied to detect genetic abnormalities such as characteristic gene fusions, aneuploidy, loss of a chromosomal region or a whole chromosome, etc.

ii) HPLC (High-Performance Liquid Chromatography)- A highly efficient screening technique used for detecting DNA sequence changes by heteroduplex analysis, scanning gene for novel mutations, genotyping of single nucleotide polymorphisms (SNPs).

iii) PCR ( polymerase chain reaction)- PCR analyses mutations that occur in many genetic diseases. PCR amplifies targeted segments of DNA through repeated cycles of denaturation, annealing, and elongation.

iv) Comparative genomic hybridization- Comparative genomic hybridisation is a technique that permits the detection of chromosomal copy number changes without the need for cell culturing. CGH can detect small deletions and duplications, but its application is limited to balanced reciprocal translocations or inversions.

v) DNA microarray analysis- The analysis measures the expression levels of large numbers of genes simultaneously or to genotype multiple regions of a genome. It can be used in tocilogical reseach, gene discovery, disease diagnosis.

                                                                                         Pharmacogenomics is the study of how genes affect a person's response to drugs. It develops rational means to optimize drug therapy, with respect to the patients genotype, to ensure maximum efficacy with minimal adverse effects. Pharmacogenomics is when scientists look at the genome of an individual to identify the genetic factors that influence their response to a drug. Pharmogenomics examines the single gene interactions with drugs. By finding these genes, genetic tests can be developed that will predict how patients are going to respond to a drug and the dose they should be given.

                                                                                    Whole-genome sequencing (WGS) is laboratory process that is used to determine nearly all of the approximately 3 billion nucleotides of an individual's complete DNA sequence, including non-coding sequence.

                                                                                    A genetic technique which sequences all pf the protein coding regions of genes in a genome is known as whole exome sequencing (WES).

                                                                                  RFLP- a technique that exploits variations in homologous DNA sequences. RFLPs can be also useful for the differential diagnosis of hereditary disease.

Microarrays- A DNA microarray is a tool used to determine whether the DNA from a particular individual contains a mutation in genes. It can detect causative infectious agents associated with a number of diseases.

SNP’s- Single nucleotide polymorphisms (SNPs) are the most common type of genetic variation among people. They can act as biological markers, helping scientists locate genes that are associated with disease.

Monoclonals- Monoclonal cells are a group of cells produced from a single ancestral cell by repeated cellular replication. Monoclonal antibodies are used in immunoassays to diagnose infections such as HIV, malaria and chlamydia. These serve as substitute antibodies that can restore, enhance or mimic the immune system's attack on cancer cells.