Genetic disorders 2

Question 1

what is achondroplasia?

Answer 1

an autosomal dominant condition that results in a form of short limbed dwarfism

Question 2

what causes achondroplasia?

Answer 2

One of two specific mutation in the FGFR3 gene

Question 3

what does the FGFR3 gene encode?

Answer 3

Encodes a protein that is involved in cell division, cell maturation, neovascularisation, wound healing, and bone growth, development and maintenance

Question 4

what is the process of allele specific PCR?

Answer 4

Involves performing two PCRs sepertely or as a multiplex reaction. One reaction utilizes a primer specific for wild-type allele, while the second utilizes a primer for the mutant allele

Question 5

what do the results of an allele specific PCR tell us?

Answer 5

Each PCR will only produce a product if the respective sequence is present. For example, if there is no band in the Mutant PCR, there is no Mutant allele, and the patient is homozygous wild-type

Question 6

what is in the PCR master mix for allele specific PCR?

Answer 6

PCR buffer
MgCl2
dNTPs
Wild type OR mutant primer
reverse primer
Platinum Taq Polymerase
MilliQ H2O

Question 7

how does haemochromatosis occur?

Answer 7

Results from a mutation in the HFE gene, which encodes an important regulator of iron uptake relative to circulating iron concentration.

Question 8

what are molecular probes?

Answer 8

Short oligonucleotide sequences coupled with fluorophores and other molecules that facilitate direct detection of the SNP mutation

Question 9

what is a basic probe?

Answer 9

Fluorescence is emitted when the Quencher is extended a specific distance away from the reporter, such as when the probe binds to its target sequence

Question 10

what is a scorpion probe?

Answer 10

The PCR primer used in conjugated with a Blocker that binds to the Quencher, looping the probe around the PCR product like a scorpion tail

Question 11

What are FRET probes?

Answer 11

Two molecular probes are used, each conjugated with fluorophores that only emit fluorescence when in close proximity to each other.

Question 12

what is a TaqMan probe?

Answer 12

Fluorescence is emitted when the fluorophore is released from the probe, which occurs when DNA polymerase degrades the probe during the PCR.

Question 13

what causes congenital adrenal hyperplasia?

Answer 13

A condition caused by a deficiency in the 21-hydroxylase enzyme involved in the synthesis of cortisol hormone. Impairment of this pathway results in excessive production of adrenocorticotropic hormone

Question 14

what type of mutation is congenital adrenal hyperplasia?

Answer 14

inherited as an autosomal recessive condition

Question 15

what is restriction fragment length polymorphism?

Answer 15

RFLP is a technique that can be used to detect variations on DNA sequences between homologous samples. This method can be used where the mutation is known to create or remove a restriction digestion site

Question 16

What is antithrombin deficiency?

Answer 16

A rare autosomal dominant condition resulting from reduced production or functional impairment of antithrombin, an important regulator of thrombin activation.

Question 17

what is sanger sequencing?

Answer 17

Involves using dideoxynucleic acids to prematurely terminated elongation during a PCR reaction. This creates PCR products of specific lengths based on where the dideoxynucleic acid is incorporated. By running separate reactions with A, T, C, and G dideoxynucleic acids, we can identify the sequence of these nucleotides based on the fragment lengths.