MOLECULAR DIAGNOSTIC CERTIFICATION
EXAM QUESTIONS AND VERIFIED ANSWERS
2026
▶ silent mutation? Answer:A mutation that changes a single nucleotide, but
does not change the amino acid created.
▶ conservative substitution? Answer:Nucleotide-pair substitution within a
protein-coding region that leads to the replacement of an amino acid by
one of similar chemical properties. Does not drastically affect protein
function
▶ non-conservative substitution? Answer:A change in the nucleotide
sequence of DNA or RNA that leads to the replacement of one amino acid
with a functionally different one, resulting in biochemical changes.
▶ nonsense substitution? Answer:premature stop codon
▶ frameshift mutation? Answer:mutation that shifts the "reading" frame of
the genetic message by inserting or deleting a nucleotide, results n
phenotypic changes
▶ Does a mutation closer to the 5' end or 3' end of the coding region likely
have more phenotypic changes?? Answer:the 5' end because the mutation
happened early on in the sequence it will affect downstream amino acids
▶ A frameshift mutation leads to a stop codon within _____________
number of codons (large/small)?? Answer:small, might have been a
evolutionary adaptation to protect cells from making long nonfunctional
proteins
▶ enzyme immunoassay? Answer:A ligand assay in which the label is an
enzyme and the binding reagent is an antibody
▶ Immunohistochemistry? Answer:detecting proteins (antigens) in cells or
tissues using antibodies tagged with fluorescent labels
, ▶ epitopes? Answer:certain regions of an antigen molecule that stimulate
immune responses
▶ antigen revival? Answer:putting sections for IHC in buffer, heat, water,
trypsin, proteinase k in order to revive the epitopes
▶ What are the two visualization methods for IHC?? Answer:colorimetric
and fluorescence (alkaline phosphotase, HRP and enzymes)
▶ High Performance Liquid Chromatography (HPLC)? Answer:A pumping
unit causes a pressurization of the mobile phase. The sample is solubilized
and injected by syringe and then the mobile phase carries the sample to
the column. the sample is separated into components and is analyzed.
Eluent can later be isolated with evaporation of solvent. Phases can sort by
size, ion strength, hydrophobicity/hydrophilicity
▶ Gas Chromatography (GC)? Answer:- Also known as vapor-phase
chromatography (VPC)
- The fluent is a gas (usually helium or nitrogen) instead of a liquid
- The adsorbent is a crushed metal or polymer inside a 30 foot column.
- The gaseous compounds travel through the column at different rates
because they adhere to the adsorbent in the column to different degrees
and will separate in space by the time they reach the end of the column.
- The injected compound must be volatile: low melting point, subsumable
solids or vaporizable liquids.
- It is common to separate molecules using GC and then to inject the pure
molecules into a masss spectrometer (run through a magnetic field, which
separates them by mass to charge ratio) for molecular weight
determination.
▶ mass spectrometry? Answer:technique based of the detection of
vaporized molecules and their ionized (charged) fragments; detection and
display of the spectra are based on the mass-to-mass charge ratios of the
ions; method is specific for qualitative analysis and useful for quantitative
analysis
▶ What two types of mass spec are used for biochemical molecules like
proteins?? Answer:ESI and MALDI
▶ SSCP? Answer:Single-strand conformation polymorphism
-uses the nature of nucleic acid to prefer the double-stranded form
EXAM QUESTIONS AND VERIFIED ANSWERS
2026
▶ silent mutation? Answer:A mutation that changes a single nucleotide, but
does not change the amino acid created.
▶ conservative substitution? Answer:Nucleotide-pair substitution within a
protein-coding region that leads to the replacement of an amino acid by
one of similar chemical properties. Does not drastically affect protein
function
▶ non-conservative substitution? Answer:A change in the nucleotide
sequence of DNA or RNA that leads to the replacement of one amino acid
with a functionally different one, resulting in biochemical changes.
▶ nonsense substitution? Answer:premature stop codon
▶ frameshift mutation? Answer:mutation that shifts the "reading" frame of
the genetic message by inserting or deleting a nucleotide, results n
phenotypic changes
▶ Does a mutation closer to the 5' end or 3' end of the coding region likely
have more phenotypic changes?? Answer:the 5' end because the mutation
happened early on in the sequence it will affect downstream amino acids
▶ A frameshift mutation leads to a stop codon within _____________
number of codons (large/small)?? Answer:small, might have been a
evolutionary adaptation to protect cells from making long nonfunctional
proteins
▶ enzyme immunoassay? Answer:A ligand assay in which the label is an
enzyme and the binding reagent is an antibody
▶ Immunohistochemistry? Answer:detecting proteins (antigens) in cells or
tissues using antibodies tagged with fluorescent labels
, ▶ epitopes? Answer:certain regions of an antigen molecule that stimulate
immune responses
▶ antigen revival? Answer:putting sections for IHC in buffer, heat, water,
trypsin, proteinase k in order to revive the epitopes
▶ What are the two visualization methods for IHC?? Answer:colorimetric
and fluorescence (alkaline phosphotase, HRP and enzymes)
▶ High Performance Liquid Chromatography (HPLC)? Answer:A pumping
unit causes a pressurization of the mobile phase. The sample is solubilized
and injected by syringe and then the mobile phase carries the sample to
the column. the sample is separated into components and is analyzed.
Eluent can later be isolated with evaporation of solvent. Phases can sort by
size, ion strength, hydrophobicity/hydrophilicity
▶ Gas Chromatography (GC)? Answer:- Also known as vapor-phase
chromatography (VPC)
- The fluent is a gas (usually helium or nitrogen) instead of a liquid
- The adsorbent is a crushed metal or polymer inside a 30 foot column.
- The gaseous compounds travel through the column at different rates
because they adhere to the adsorbent in the column to different degrees
and will separate in space by the time they reach the end of the column.
- The injected compound must be volatile: low melting point, subsumable
solids or vaporizable liquids.
- It is common to separate molecules using GC and then to inject the pure
molecules into a masss spectrometer (run through a magnetic field, which
separates them by mass to charge ratio) for molecular weight
determination.
▶ mass spectrometry? Answer:technique based of the detection of
vaporized molecules and their ionized (charged) fragments; detection and
display of the spectra are based on the mass-to-mass charge ratios of the
ions; method is specific for qualitative analysis and useful for quantitative
analysis
▶ What two types of mass spec are used for biochemical molecules like
proteins?? Answer:ESI and MALDI
▶ SSCP? Answer:Single-strand conformation polymorphism
-uses the nature of nucleic acid to prefer the double-stranded form
