Genotyping of TAS2R38 (PTC) gene by PCR-RFLP and DNA sequencing

What is the T2T38 receptor responsible for?

Mediating the bitter taste of PTC

What are the two types of TAS2R38 genotypes?

PAV-type and AVI-type

Is the ability to taste PTC a dominant trait?

Yes

What are the three common SNPs in the TAS2R38 gene?

rs713598, rs1726866, rs10246939

What is the function of PCR-RFLP?

Detecting nucleotide polymorphisms

What is the principle of DNA purification by absorption to silica surface?

DNA selectively absorbs to silica in the presence of high salt concentration

What is the purpose of the QIAquick PCR purification kit?

Purifying DNA from cells or agarose gel pieces

Which buffer in the QIAquick PCR purification kit promotes DNA binding to the silica matrix?

Buffer PB

What is anion-exchange chromatography used for in DNA purification?

Separating DNA from RNA, proteins, carbohydrates, and other metabolites

How is DNA precipitated using salt and ethanol?

Salt and ethanol remove water around DNA, making it less hydrophilic and promoting DNA aggregation

What is the Sanger method also known as?

Chain termination method

How does the Sanger method work?

Incorporation of dideoxyribonucleotides (ddNTPs) leads to chain termination during DNA synthesis

How are sequencing products separated in the Sanger method?

By electrophoresis on a slab gel or capillary

What is the principle of cycle sequencing?

It uses the Sanger sequencing technique with repeated cycles of DNA amplification

What is the purpose of the dye-labeled terminator in cycle sequencing?

To identify the terminal bases during chain termination

What is the temperature range for annealing in cycle sequencing?

50-55°C

What happens during the extension step in cycle sequencing?

DNA polymerase adds dNTPs and a trace amount of ddNTPs, leading to chain termination

What is the purpose of electrophoresis in cycle sequencing?

To separate the extension products based on size

What is the principle of DNA sequencing by capillary electrophoresis?

Different fluorescent labels on terminators allow for the identification of the terminal bases

What is the relationship between haplotypes and TAS2R38 polymorphisms?

Haplotypes are specific combinations of alleles from different polymorphisms that tend to be inherited together

What are the functional haplotypes of TAS2R38?

PAV, AAV, PVI, AAI

What is the non-functional haplotype of TAS2R38?

AVI

What is the purpose of PCR primers in PCR-RFLP?

To amplify a DNA fragment containing the polymorphic sites

What is the restriction enzyme used in PCR-RFLP?

Fnu4HI

What is the purpose of gel electrophoresis in PCR-RFLP?

To analyze and differentiate the alleles by their fragment lengths