Question

what are some methods of genetic screening at the molecular level? (in depth)

Answer 1

Answer :-

PCR :- A common technique for making numerous copies of short DNA parts from a very small sample of genetic material is polymerase chain reaction (PCR). This process is called the "amplifying" DNA and enables the identification or measurement of specific genes or regions of interest.
Often this process is used to clone DNA, so that it can be sequenced or examined using other techniques. It is often used to help find genetic variants known to cause such illnesses, such as cancer-related ones or genetic disorders.

DNA sequencing :- DNA sequencing refers to the determination of the sequence of the bases[ adenine (A), thymine (T), cytosine (C) and guanine (G)] that make up DNA. Sequencing helps physicians to determine whether a gene or region that controls a gene (regulatory DNA region) involves modifications or variants linked to a disease.

Sanger sequencing :- Sanger sequencing has been the gold standard for clinical DNA sequencing for many years to look at individual genes or some genes at a time. This depends on a special chemical that identifies a different colored fluorescent dye for each DNA nucleotide, depending on which base this carries A, T, C, or G.

Fluorescence in situ hybridization (FISH) :- A special technique commonly called FISH for short can be used to show changes in chromosomes that result from genetic variations. A gene segment in a chromosome may be made to "light up" or fluoresce when bound by a specific probe. By using more than one sample at a time, cytogeneticists may compare to see if the samples are in their normal position or have moved to a new location on a different chromosome, or if there are more or less copies of a sample than in a normal cell.

Gene expression profiling :- the analysis of gene expression looks at which genes are turned on or off in the cells. Gene expression is the process by which different proteins are generated by the information found within the genes. Different tissues express different sets of genes according to their location within the body. The gene information is used to construct a basis for the creation of RNA. Afterwards, RNA undergoes complex modifications to build the protein the cell requires. Gene expression studies in a person's tissue sample analyze the RNA to assess what genes are actively producing proteins.